AUTHOR AND EDITOR INFORMATION
Section 1 of 10
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Author: Mark Jeffrey Noble, MD, Consulting Staff, Urologic Institute, Cleveland Clinic Foundation
Mark Jeffrey Noble is a member of the following medical societies:
American College of Surgeons,
American Medical Association,
American Urological Association,
Kansas Medical Society,
Sigma Xi, Society of University Urologists, and
Southwestern Oncology Group
Coauthor(s):
Milton Lakin, MD, Head, Section of Medical Urology, Urological Institute, Cleveland Clinic
Editors:
Leonard Gabriel Gomella, MD, FACS, The Bernard W Godwin Professor of Prostate Cancer Chairman, Department of Urology, Associate Director of Clinical Affairs, Kimmel Cancer Center, Thomas Jefferson University;
Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine;
J Stuart Wolf, Jr, MD, FACS, David A Bloom Professor of Urology, Director, Division of Minimally Invasive Urology, Department of Urology, University of Michigan Medical Center;
Stephen W Leslie, MD, FACS, Founder and Medical Director of the Lorain Kidney Stone Research Center, Clinical Assistant Professor, Department of Urology, Medical College of Ohio
Author and Editor Disclosure
Synonyms and related keywords: premature ejaculation, PE, primary premature ejaculation, secondary premature ejaculation,
sexual dysfunction,
ED,
erectile dysfunction, rapid ejaculation, premature ejaculator, rapid ejaculator, performance anxiety, performance pressure,
impotence,
erection problem, rapid sexual release, primary PE, secondary PE, anorgasmia, lifelong premature ejaculation, acquired premature ejaculation
Background
Premature ejaculation (PE) is the most common sexual dysfunction in men younger than 40 years. Most professionals who treat premature ejaculation define this condition as the occurrence of ejaculation prior to the wishes of both sexual partners. This broad definition thus avoids specifying a precise duration for sexual relations and reaching a climax, which is variable and depends on many factors specific to the individuals engaging in intimate relations. An occasional instance of premature ejaculation might not be cause for concern, but, if the problem occurs with more than 50% of attempted sexual relations, a dysfunctional pattern usually exists for which treatment may be appropriate.
To clarify, a male may reach climax after 8 minutes of sexual intercourse, but this is not premature ejaculation if his partner regularly climaxes in 5 minutes and both are satisfied with the timing. Another male might delay his ejaculation for a maximum of 20 minutes, yet he may consider this premature if his partner, even with foreplay, requires 35 minutes of stimulation before reaching climax. If intercourse is the method of sexual stimulation for the second example and the male climaxes after 20 minutes of intercourse and then loses his erection, satisfying his partner (at least with intercourse), who needs 35 minutes to climax, is impossible.
Because many females are unable to reach climax at all with vaginal intercourse (no matter how prolonged), this situation may actually represent delayed orgasm for the female partner rather than premature ejaculation for the male; the problem can be either or both, depending on the point of view. This highlights the importance of obtaining a thorough sexual history from the patient (and preferably from the couple).
The human sexual response can be divided into 3 phases: desire (libido), excitement (arousal), and orgasm. The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) classifies sexual disorders into 4 categories: (1) primary, (2) general medical condition–related, (3) substance-induced, and (4) not otherwise specified. Each of the 4 DSM-IV categories has disorders in all 3 sexual phases.
Premature ejaculation may be primary or secondary. Primary applies to individuals who have had the condition since they became capable of functioning sexually (ie, postpuberty). Secondary indicates that the condition began in an individual who previously experienced an acceptable level of ejaculatory control, and, for unknown reasons, he began experiencing premature ejaculation later in life. With secondary premature ejaculation, the problem does not relate to a general medical disorder, and it is usually not related to substance inducement, although, rarely, hyperexcitability might relate to a psychotropic drug and resolves when the drug is withdrawn. Premature ejaculation fits best into the category of not otherwise specified because no one really knows what causes it, although psychological factors are suggested in most cases.
Pathophysiology
Premature ejaculation is believed to be a psychological problem and does not represent any known organic disease involving the male reproductive tract or any known lesions in the brain or nervous system. The organ systems directly affected by premature ejaculation include the male reproductive tract (ie, penis, prostate, seminal vesicles, testicles, and their appendages), the portions of the central and peripheral nervous system controlling the male reproductive tract, and the reproductive organ systems of the sexual partner (for the purpose of this discussion, the partner is assumed to be female) that may not be stimulated sufficiently to achieve orgasm.
If the premature ejaculation occurs so early that it happens before commencement of sexual intercourse and the couple is attempting pregnancy, then pregnancy is impossible to achieve unless artificial insemination is used. Perhaps the most affected organ system is the psyche of the partners. Both partners are likely to be dissatisfied emotionally and physically by this problem.
Premature ejaculation has historically been considered a psychological disorder. One theory is that males are conditioned by societal pressures to reach climax in a short time because of fear of discovery when masturbating as teenagers or during early sexual experiences "in the back seat of the car" or with a prostitute. This pattern of rapid attainment of sexual release is difficult to change in marital or long-term relationships. The fact that female arousal and orgasm require more time than male arousal is being increasingly recognized, and this may result in increased recognition and definition of premature ejaculation as a problem.
Some have questioned whether premature ejaculation is purely psychological. A number of investigators have found differences in nerve conduction/latency times and hormonal differences in men who experience premature ejaculation compared with individuals who do not. The theory is that some men have hyperexcitability or oversensitivity of their genitalia, thus preventing down-regulation of their sympathetic pathways and delay of orgasm.
One might find some logical sense, from an evolutionary point of view, that males who can ejaculate rapidly would be more likely to succeed in fertilizing a female than males who require prolonged stimulation to reach climax. (This applies to prehistoric evolutionary development; little, if any, human evolution has occurred over the last 5000 y.) The genes of a person who ejaculates rapidly (but not so rapidly that ejaculation occurs before intromission) would be more likely to be passed on to succeeding generations. The male who does not complete the fertilizing process quickly might be pushed away or killed by a competing male because of his obvious vulnerability during intercourse.
Frequency
United States
The prevalence rate of premature ejaculation in American males is estimated to range from 30-70%. The National Health and Social Life Survey (NHSLS) indicates a prevalence of 30%, which is fairly steady through all adult age categories. (In contrast, erectile dysfunction [ED] rises in prevalence with increasing age). However, various surveys have shown that many men do not report premature ejaculation to their physician. This may be because of embarrassment or a feeling that no treatment is available for the problem. Some men might not even perceive premature ejaculation as a medical problem. Such survey data suggest that the percentage of men who experience premature ejaculation at some point in their lives is almost certainly more than the 30% reported in the NHSLS.
International
Estimates for European countries and India mirror the prevalence in the United States. The prevalence in other parts of Asia, Africa, Australia, and elsewhere is unknown.
Mortality/Morbidity
No known direct morbidity or mortality results from premature ejaculation. Indirectly, premature ejaculation may alter self-esteem, cause marital dysfunction, and may be a factor in depression with its obvious consequences.
Race
Although no reproducible data exist on major differences between racial groups with respect to the incidence or prevalence of premature ejaculation, a few recent surveys suggest that some racial variation may exist with respect to this condition. One recent telephone survey (Carson and associates) found in interviews of 1320 men without ED that 21% of non-Hispanic African Americans reported premature ejaculation, while 29% of Hispanics and 16% of non-Hispanic whites reported premature ejaculation. An analysis by Laumann et al of the NHSLS found that premature ejaculation was more prevalent among African American men (34%) and white men (29%) than among Hispanic men (27%). However, drawing firm conclusions from these data is difficult in view of the small number of such studies and lack of suitable controls.
Sex
Premature ejaculation is a condition that only affects males.
Age
Premature ejaculation can occur at virtually any age in an adult man's life. As a reported condition, it is most common in younger men (aged 18-30 y) but may also occur in conjunction with secondary impotence in men aged 45-65 years.
History
The history of the patient's premature ejaculation is helpful because it ultimately guides the treatment that is best suited to the patient (and his partner). One needs to focus on whether premature ejaculation is lifelong (ie, primary) or acquired (ie, secondary) and assess the severity of the problem.
For completeness, a general medical history should be taken to screen for other medical conditions that might be relevant. For example, if the patient has angina and this causes fear of a myocardial infarction during sexual activity, he might present with premature ejaculation when the actual underlying problem is his cardiac disease and his mental insecurity regarding his cardiac disease. Resolution of the cardiac problem usually solves the premature ejaculation, with no specific therapy for the premature ejaculation. For the purpose of this discussion, the patient is assumed to be healthy, and sexual dysfunction is the only significant problem.
If the patient has always experienced premature ejaculation from the time he began coitus, then he has primary premature ejaculation. If he had successful coital relationships in the past, yet began experiencing premature ejaculation with the current relationship, then he has secondary premature ejaculation. In most cases, secondary premature ejaculation is easier to treat and has a better prognosis.
Primary premature ejaculation
In addition to the general medical history, inquire about any prior psychological difficulties because males with primary premature ejaculation have a higher incidence of associated psychiatric conditions than that found in the general population. The history should include questions about the patient's early sexual experiences. Did he experience a traumatic sexual episode as a child or teenager? An example might be discovery by a parent during masturbation, with subsequent feelings of guilt. Alternatively, the patient may have been punished or threatened with punishment for masturbation. Inquire about the patient's family relationships while he was growing up. How did he relate to his mother, father, brother(s), sister(s)? Does his family have a history of incest or sexual assault? Males can be sexually assaulted by other males and, in rare instances, by females, including siblings. What were peer relationships like? Did he have other male friends, any female friends? How does he regard himself with respect to peers (eg, inferior, superior, athletic, frail, more intelligent, less intelligent)? Does the patient have any difficulties with work (or school, if still a student)? What is the patient's general attitude toward sex (ie, whether it is regarded as dirty), and what is the patient's sexual preference, fantasy, and arousal pattern? Did the patient have a strict religious upbringing? If so, what was the teaching about sex? If the premature ejaculation began with an initial nonmarital relationship, does he feel guilt about this? If the first coital experience was within a marital relationship that involved premature ejaculation from the start, inquire about premarital, noncoital sexual play between the partners. Ask about the sexual attitude and response of the female partner; if she is having a problem, such as dyspareunia, it could relate to the male's problem or may have preceded it. What is the nonsexual part of the relationship like? Does the couple fight or are they going through a power struggle? If the sexual partner is not present, inquire as to why (ie, whether the partner is not supportive or is blaming him). Clues from these and similar questions usually point toward causation factors that may be addressed specifically with therapy.
Secondary premature ejaculation
In addition to a general medical history, the history should include details about prior relationships in which premature ejaculation was not a problem for this individual and any prior relationships in which transient episodes of premature ejaculation occurred. In the current relationship, was premature ejaculation always a problem or did it start after an initial time frame when coitus was satisfactory to both partners? Inquire specifically as to the quality of the relationship with respect to nonsexual factors. Do the partners get along on most issues, or is conflict present? Who is dominant in the relationship, or is the relationship generally equal? Is the female partner in the office with the male patient? If not, ask why. Possibly, she regards the problem as only his problem and not a problem of the couple, which may be an important clue. Does he have an impotence problem? If erectile dysfunction (ED) is present, did this begin after the problem with premature ejaculation or before? If ED is not present, what is the general timing for the male (ie, commencement of intromission to climax)? Can actual coitus be achieved, or does premature ejaculation prevent this? Is the patient experiencing premature ejaculation with self-stimulation (ie, masturbation), with nonintercourse stimulation by the partner, or just with coitus? What is the time required for the female partner to reach climax? Can she reach climax with intercourse, or does she require direct clitoral stimulation (oral or manual) to be able to climax? If ED is present but began after the premature ejaculation, then treatment of both conditions may be required; sometimes, the ED resolves when the patient gains confidence in controlling his ejaculation. If the ED started initially, then the premature ejaculation may be a secondary sexual dysfunction, which resolves when the patient is confident in being able to maintain his erection. Clarification of these and other factors usually proves very helpful when arriving at a treatment plan.
Physical
Physical examination findings are normal in males when premature ejaculation is the only presenting condition.
Causes
The cause of premature ejaculation is considered psychological, although no one really knows.
Primary premature ejaculation
In primary premature ejaculation, in which the male has never experienced sexual relations without also experiencing premature ejaculation, a deep-seated emotional disturbance (see History) may be present and the causes may be multiple. Sometimes, the behavior is a conditioned response resulting from teen masturbation practices (see Introduction), but, sometimes, the patient has deep anxiety about sex that relates to one or more traumatic experiences encountered during development. Examples may include family incest, sexual assault, conflict with one or both parents, or other serious disturbances. In most cases, a primary care physician or a urologist should consult with a psychiatrist, psychologist, or other professional in cases of primary premature ejaculation.
Secondary premature ejaculation
With regard to secondary premature ejaculation, some type of performance anxiety is often a major factor. Performance pressure (ie, fear of failure to satisfy the partner) can arise from various precipitating events. ED is a common precipitating event. If the male is afraid his erection will not last, because of either actual instances of previous ED or imagined failure of his erection, this may precipitate premature ejaculation. The patient may have used the phrase, "Honey, you excited me so much I just could not hold back," which might be a way for him to avoid admitting to the humiliation of being unable to keep his erection throughout intercourse. If he climaxes quickly, he then has an excuse to justify his inability to maintain his erection. However, a careful history (see History) is needed because the situation may be complex. Perhaps ED is not a part of the problem. Possibly, his partner has belittled him with comments such as "You must not be much of a man, since you cannot stay hard until I am satisfied." In addition, she actually may have difficulty achieving climax through intercourse and may require direct clitoral stimulation to reach a climax. If she does not communicate this to him (and she may conceal it because of feelings about her own inadequacy), then he will always fail to provide coital satisfaction for her. Because most physicians are not trained sex therapists, sorting out conflicts in the relationship and then referring couples for counseling to professionals with experience and training in that area is important. If a physician has some training or experience in the treatment of premature ejaculation and is comfortable managing the problem, then the physician may choose to begin treatment (eg, counseling, medication, both). If the patient does not respond favorably or if the physician is not comfortable with the treatment of premature ejaculation, then referral to a sex therapist, psychologist, or psychiatrist is the next step.
Other Problems to be Considered
Consider anorgasmia or severely delayed orgasm in the female partner, in which the word delayed is a relative term because the average time to climax for a female varies but averages 12-25 min according to many studies. If a female partner requires 3 hours to reach climax, this is well outside the norm. In extreme cases of delayed or difficult orgasm in the female partner, nearly all men would be considered to have premature ejaculation. The partner's sexual response must be considered.
Consider a rare adverse effect from a psychotropic drug. If the premature ejaculation problem started in association with some time relationship to commencing the drug and premature ejaculation ceases when the drug is withdrawn, one should strongly consider that the two are related.
Some men may confuse premature ejaculation with what is colloquially referred to as "pre-come," ie, pre-ejaculate, the lubricating fluids produced by Cowper glands and other glands during the excitement phase of sexual stimulation. A detailed sexual history should clarify this matter and should enable reassurance of the male as to what is actually happening.
Erectile dysfunction (ED) may be a clinical symptom of some men who are actually experiencing premature ejaculation. Differentiating between the 2 problems is important.
Lab Studies
In males with premature ejaculation and no other medical problems, no specific conventional laboratory tests aid or affect treatment. Checking a serum testosterone (free and total) level and prolactin level may be appropriate if premature ejaculation is observed in conjunction with an impotence problem. If depression or other conditions coexist, laboratory studies specific to depression or to another medical or psychological problem are appropriate. Some investigators are performing vibrational threshold testing on volunteer subjects; others are using nerve conduction times, somatosensory latency testing, or both. A few investigators are evaluating the hypothalamic-pituitary-gonadal axis, some are testing melatonin levels, and some are measuring levels of carbon monoxide and nitric oxide (mediators of male sexual function). However, all such determinations must be considered experimental at this time, and they have no applicability to current clinical practice.
Medical Care
Medical treatment for premature ejaculation includes several options. Any serious primary medical condition (eg, angina) should be treated; for the purpose of the following discussion, the male is assumed to be healthy and premature ejaculation is assumed to be his only problem. In addition, any accompanying erection problem can be treated with various methods with excellent success (see Erectile Dysfunction) and thus, only passing reference is made to treatment of erectile dysfunction (ED) that may accompany the premature ejaculation problem.
Including the female partner as much as possible in the treatment and counseling sessions is important to achieve the best outcome. The first step for treatment of premature ejaculation is to relieve any underlying performance pressure on the male.
Assuming that premature ejaculation occurs when intercourse is attempted, instruct the couple that intercourse should not be attempted until premature ejaculation is treated. The male may use manual stimulation, oral sex, or other means to satisfy the female partner in the meantime. If the male always experiences ejaculation with initial sexual excitement or early foreplay, this is a serious problem and probably indicates primary premature ejaculation (the history should reveal this), which then most likely requires treatment in conjunction with a mental health care professional. These more difficult cases should be screened out.
The couple should then be instructed on sexual therapy, such as the stop-start or squeeze-pause technique popularized by Masters and Johnson.
The female partner should slowly begin stimulation of the male and should stop as soon as he senses a feeling of excessive excitement that may lead to ejaculatory inevitability. Then, she should administer a firm compression of the penis just behind the glans, pressing mainly under the penis. This should be uncomfortable but not painful. Stimulation then should begin again after the male has a feeling that the ejaculation is no longer imminent. The process should be repeated and practiced at least 10 or more times. Gradually, most males find this technique helps decrease the impending inevitable need to ejaculate. After a period of practicing this method, the couple can sit facing each other, with the woman's legs crossing on top of the male's legs. She can stimulate him by manipulating his penis close to, then with friction against, her vulval area. Each time he senses excessive excitement, she can apply the squeeze and stop all stimulation until he calms down enough for the process to be repeated. Finally, coitus may be attempted, with the female partner in the superior position so that she may withdraw immediately and again apply a squeeze to remove his urge to climax. Most couples find this technique to be highly successful. It can also help the female partner to be more aroused and can shorten her time to climax because it constitutes a form of extended foreplay in many cases.
Another therapeutic modality is the use of desensitizing cream for the male.
In Korea and other areas of the Far East, SS Cream (a combination of 9 ingredients, mainly herbal) has been shown to desensitize the penis, decrease the vibratory threshold, and help men with premature ejaculation to significantly delay their ejaculatory response. Unfortunately, SS Cream is not yet approved by the US Food and Drug Administration (FDA), but simple combinations of lidocaine cream or related topical anesthetic agents can be used with similar effects and they are safe as long as the patient has no history of allergy to the substance.
If the male is relatively young and he can achieve another erection in a few minutes following an episode of premature ejaculation, he may find that his control is much better the second time.
Some therapists advise young men to masturbate (or have their partner stimulate them rapidly to climax) 1-2 hours before sexual relations are planned. The interval for achieving a second climax often includes a much longer period of latency, and the male can usually exert better control in this setting. In an older man, such a strategy may be less effective because the older man may have difficulty achieving a second erection after his first rapid sexual release. If this occurs, it can damage his confidence and may result in secondary impotence.
The most effective pharmacologic modality found to aid men with premature ejaculation is a drug from the selective serotonin reuptake inhibitors (SSRIs) class, drugs which are used normally as antidepressants in the clinical setting.
Some tricyclic antidepressants with SSRI-like activity also achieve the same result. Many of these agents have been found to have, as a side effect, a tendency to cause both male and female patients to experience a significant delay in reaching orgasm. For this reason, medications with SSRI side effects have been used in men who experience premature ejaculation.
Surgical Care
No recommended surgical treatment exists for premature ejaculation.
Consultations
Consultation with a sex therapist, psychologist, or psychiatrist may prove helpful if the primary care physician or urologist cannot provide successful treatment or does not have the time to explore psychological issues and implement behavioral techniques (eg, squeeze-pause). If the primary care physician or urologist is not experienced in treating premature ejaculation or is uncomfortable with treatment, then early referral should take place (to a sex therapist, psychologist, or psychiatrist). Some physicians are comfortable implementing medication therapy but not behavioral therapy. The patient should be offered all treatment options as with any medical condition, and the physician should proceed with referral for those option(s) considered to require more specialized help than the physician can provide. For men who may be experiencing a severe emotional disturbance that is an underlying factor to premature ejaculation, referral to a mental health professional is most appropriate. Diagnosis and treatment of the various psychological factors that manifest partly as premature ejaculation are beyond the scope of this discussion.
No drug is approved by the FDA for the treatment of premature ejaculation. However, numerous studies have shown that selective serotonin reuptake inhibitors (SSRIs) and drugs with SSRI-like side effects are safe and effective to treat this condition, and many physicians use these agents for this purpose. SSRIs have been the most successful agents in delaying the too-rapid response in men who experience premature ejaculation. Desensitizing creams containing local anesthetic agents can also be useful for some men with premature ejaculation. These agents are not approved by the FDA specifically for this use, but they are believed to be of at least some efficacy and are a minimal-risk option for patients.
Premature ejaculation that relates to erectile dysfunction (ED) may resolve if ED is treated successfully. Drugs for the treatment of ED include sildenafil (Viagra), vardenafil (Levitra), tadalafil (Cialis), alprostadil (Caverject, Muse), and, possibly, SSRI antidepressants (if depression is causing the ED). Details on drugs for the treatment of ED are included in the article on impotence (see Erectile Dysfunction).
If a patient does not have premature ejaculation but has depression-related ED only, the use of a drug with minimal adverse sexual effects (incidence <1%) such as bupropion HCl (Wellbutrin) or venlafaxine HCL (Effexor) might be a consideration in an effort to avoid creating a problem with delayed ejaculation or even anorgasmia. However, if the patient has significant premature ejaculation, ED, and depression, an added benefit of an antidepressant with SSRI side effects is the possibility that the premature ejaculation is also helped.
Drug Category: Selective serotonin reuptake inhibitors
Mechanism of action is linked to their inhibition of neuronal uptake of serotonin in the CNS. Various animal studies suggest that SSRIs have weak effects on norepinephrine and dopamine neuronal reuptake. They do not antagonize adrenergic (eg, alpha1-adrenergic, alpha2-adrenergic, beta-adrenergic), cholinergic, GABA, dopaminergic, histaminergic, serotonergic (5HT 1A, 5HT 1B, 5HT 2), or benzodiazepine receptors; therefore, they have fewer adverse anticholinergic effects than tricyclic antidepressants.
SSRIs have been observed to cause sexual side effects, the most common being delay in sexual climax for both males and females. In most cases, females require quite a bit more time to reach climax than males; therefore, delayed climax caused by an SSRI becomes an adverse effect in women. Often, the frustration and discouragement of the inability to reach orgasm induce a pattern of sexual avoidance in many females, and a corresponding decrease in libido or sexual excitement (lubrication) develops in these individuals. In males, too-rapid orgasm can cause some of the same patterns of sexual avoidance and decreased libido; thus, determining the primary problem when instituting therapy is important. Sertraline (Zoloft), paroxetine (Paxil), and fluoxetine (Prozac) are useful SSRIs for treating premature ejaculation.
The optimal medical treatment for premature ejaculation has not been established, but, in the author's experience, single dosing prior to sexual relations can work for some males, while in others, achieving a blood level through daily use of the medication may be necessary, as in the treatment of clinical depression. Obviously, if single dosing is successful, therapy is simpler and is associated with fewer adverse effects. Therefore, this may be the preferred initial therapy. The dose may be increased in step-wise fashion until a therapeutic effect is achieved or until the maximum daily recommended dose is reached. No exact schedule of increased dosing has been determined, and the experience of the physician, response of the individual patient, adverse effects experienced by the patient, and other general medical considerations should be the guiding factors.
If one SSRI fails to help the patient, using a second choice certainly is reasonable. However, if the second choice fails, the author's experience is that a third choice is not likely to benefit the patient. As with treatment for depression, if a patient has been on the medication for 6 weeks at maximal dose with no improvement, then the likelihood is remote that a more prolonged course of therapy with a particular drug would be successful. No reason exists for not combining medication with behavioral modification therapy, desensitizing creams, or both; additive effects or even synergy from several simultaneous treatments can occur. If all treatment fails, then the only options are for the patient to see a different health care professional, if he wishes, or for him to accept his condition as being untreatable with currently available therapeutic options.
Drug Name Sertraline (Zoloft)
Description Potent SSRI used to treat premature ejaculation. Improvement may not be evident until at least 3 wk following initiation of treatment. If no benefit with respect to premature ejaculation after 6 wk or if adverse effects become troublesome, discontinue in favor of alternative treatment.
Adult Dose 50 mg PO 2-12 h before sexual relations; alternatively, 50 mg/d PO; gradually titrate to response; not to exceed 200 mg/d
Pediatric Dose Not established
Contraindications Documented hypersensitivity; concomitant MAOIs or use within 14 d
Interactions Increases toxicity of MAOIs, diazepam, tolbutamide, and warfarin; additive CNS effects with alcohol, antidepressants, opioid analgesics, sedatives, and hypnotics; suspension contains alcohol and, therefore, is contraindicated in patients taking disulfiram (Antabuse)
Pregnancy C - Safety for use during pregnancy has not been established.
Precautions Caution in recent MI or unstable heart disease; hyponatremia; although minimal adverse anticholinergic effects (compared with TCAs), use with caution in glaucoma, bladder outlet obstruction, chronic constipation, and other conditions in which adverse anticholinergic effects may exacerbate symptoms; caution in patients with moderate-to-severe renal or hepatic impairment, because of excessive blood level accumulation, adjust dose accordingly; does not impair motor or cognitive ability with respect to performance of complex tasks, nor does it cause somnolence, but any drug affecting the CNS may cause drowsiness, and driving and performance of other tasks requiring alertness and concentration should be avoided; seizures are rare, use with caution in preexisting seizure disorder; when used for premature ejaculation (off-label), patients with clinical depression should be treated by a mental health care professional, potential for depressed patients to commit suicide; priapism has been (rarely) reported
Drug Name Paroxetine (Paxil)
Description Potent SSRI antidepressant used to treat premature ejaculation. Improvement may not be evident until at least 3 wk following initiation of treatment. If no benefit (with respect to premature ejaculation) after 6 wk or adverse effects become troublesome, medication should be discontinued in favor of an alternative treatment.
Adult Dose 20 mg PO 2-12 h before sexual relations; alternatively, 20 mg/d PO, gradually titrate to response; not to exceed 40 mg/d
Pediatric Dose Not established
Contraindications Documented hypersensitivity; concomitant MAOIs or use within 14 d
Interactions Phenobarbital and phenytoin decrease effects; alcohol, cimetidine, sertraline, phenothiazines, and warfarin increase toxicity; additive CNS depressant effects with other antidepressants, opioid analgesics, sedatives, and hypnotics; increases toxicity of MAOIs
Pregnancy B - Usually safe but benefits must outweigh the risks.
Precautions Caution in recent MI or unstable heart disease; hyponatremia; although minimal adverse anticholinergic effects (compared with TCAs), use with caution in glaucoma, bladder outlet obstruction, chronic constipation, and other conditions in which adverse anticholinergic effects may exacerbate symptoms; also caution in moderate-to-severe renal or hepatic impairment, because of excessive blood level accumulation (adjust dose accordingly); does not impair motor or cognitive ability with respect to performance of complex tasks, nor does it cause somnolence, but any drug affecting the CNS may cause drowsiness, and driving and performance of other tasks requiring alertness and concentration should be avoided; seizures are rare; caution in preexisting seizure disorder; when used for premature ejaculation (off-label), patients with clinical depression should be treated by a mental health care professional; potential for depressed patients to commit suicide; priapism has been (rarely) reported
Drug Name Fluoxetine (Prozac)
Description Potent SSRI used to treat premature ejaculation. Improvement may not be evident until at least 3 wk following initiation of treatment. If no benefit with respect to premature ejaculation after 6 wk or if adverse effects become troublesome, discontinue in favor of alternative treatment.
Adult Dose 5-60 mg/d PO; most clinicians begin at 10-20 mg/d (in one dose or in two divided doses), or taken 2 h prior to intercourse as single-dose therapy; total daily dose not to exceed 80 mg/d
Pediatric Dose Not established
Contraindications Documented hypersensitivity; concomitant MAOIs or use within 14 d; thioridazine within 5 wk of discontinuation
Interactions Phenobarbital and phenytoin decrease effects; alcohol, cimetidine, sertraline, phenothiazines, and warfarin increase toxicity; additive CNS depressant effects with other antidepressants, opioid analgesics, sedatives, and hypnotics; increases toxicity of MAOIs; can alter levels of antidiabetic drugs (they may need adjustment); can alter levels of warfarin, digitalis, or both; may increase benzodiazepine, phenytoin, and carbamazepine levels; increased adverse effects with tryptophan; lithium levels can increase or decrease and need monitoring; may potentiate drugs metabolized by CYP2D6, antipsychotics (eg, haloperidol, clozapine), or other antidepressants; avoid alcohol, during or within 14 d of MAOIs, or within 5 wk of thioridazine discontinuation; caution with drugs that impair hemostasis (eg, nonselective NSAIDS, aspirin, warfarin) because of increased risk of bleeding
Pregnancy C - Safety for use during pregnancy has not been established.
Precautions Discontinue upon unexplained allergic reaction; monitor for symptoms of mania or hypomania; caution with diseases or conditions that could affect metabolism or hemodynamic responses, diabetes, history of seizures, suicidal tendencies; altered platelet function and hyponatremia reported; monitor for clinical worsening or suicidality, especially at initiation of therapy or dose changes; avoid abrupt withdrawal; monitor for discontinuation symptoms
Drug Category: Tricyclic antidepressants
Drugs with SSRI-like side effects (ie, delaying sexual climax) can be used to treat premature ejaculation. The tricyclic antidepressant most studied for premature ejaculation is clomipramine (Anafranil). Many investigators find that clomipramine is more effective for premature ejaculation than many SSRIs.
Drug Name Clomipramine (Anafranil)
Description Inhibits membrane pump mechanism responsible for uptake of norepinephrine and serotonin in adrenergic and serotonergic neurons. These actions are believed to be responsible for its antidepressant activity. Inhibition of serotonin probably gives the SSRI-like activity that produces side effects (eg, inhibition of ejaculation).
Adult Dose 50 mg PO 2-12 h before sexual relations; alternatively, 50 mg/d PO
Pediatric Dose Not established
Contraindications Documented hypersensitivity; recent MI; do not use within 14 d of MAOIs administration
Interactions Barbiturates, phenytoin, and carbamazepine decrease effects; increases effects of anticholinergics, sympathomimetics, alcohol, and CNS depressants; increased toxicity of MAOIs
Pregnancy C - Safety for use during pregnancy has not been established.
Precautions Caution in preexisting seizure disorders; recent MI or unstable heart disease; in hepatic or renal impairment, adjust dose accordingly; constipation; glaucoma; hyponatremia
Drug Category: Topical anesthetic agents
These agents may reduce penile sensitivity and excitability and delay ejaculation. Condoms also reduce male sensitivity, yet no evidence exists that wearing a condom helps successfully treat premature ejaculation. Topical anesthetic cream is probably the lowest-risk medication that can be used for premature ejaculation, with no adverse systemic effects in the absence of prior hypersensitivity to the medication (patient or partner). Usually, no contraindication exists for combined therapy with topical anesthetics, antidepressants, and behavioral therapy.
Drug Name Lidocaine 2.5% and prilocaine 2.5% (EMLA)
Description Applied to intact skin under an occlusive dressing, provides dermal analgesia. Effectiveness of this when applied to the penis is not proven; an occlusive dressing might also be difficult unless the penis is covered with a condom or cellophane. Lidocaine and prilocaine are amide-type local anesthetic agents. Both lidocaine and prilocaine stabilize neuronal membranes by inhibiting the flow of certain ions required for the initiation and conduction of nerve impulses, thus producing local anesthesia.
Adult Dose Apply liberally to entire penile skin 1-2 h before sexual intercourse; effect may last up to 1 h or longer after occlusive dressing or condom is removed. Consider removal of any remaining excess medication from penis prior to intercourse to avoid reduction in partner's vaginal sensitivity.
Pediatric Dose Not established
Contraindications Documented hypersensitivity in patient or partner
Interactions None reported
Pregnancy B - Usually safe but benefits must outweigh the risks.
Precautions Cautious application to skin with rash, skin eruption, or other skin irritation
Drug Category: Phosphodiesterase type 5 inhibitor (PDE5 inhibitor)
Some recent studies have demonstrated that sildenafil (Viagra) and other PDE5 inhibitors in combination with SSRIs provide better results when used to treat premature ejaculation than use of SSRIs alone. The reason for this is unknown, but the mechanism may be, in part, that an improved erection (firmness, duration, or both) resulting from the PDE5 inhibitor provides inhibition of ejaculation via down-regulation of receptors involved in somatosensory latency times. A reduction in performance anxiety may exist on a subconscious level. Regardless of the mechanism, PDE5 inhibitors have been found to be safe and effective as an adjunct to treating premature ejaculation in men for whom no contraindication otherwise exists. The only PDE5 inhibitor studied recently to any degree is sildenafil (Viagra); others may work as well, but insufficient data exist at this time to list them.
Drug Name Sildenafil (Viagra)
Description Sildenafil is FDA-approved for the treatment of erectile dysfunction (ED) but not specifically for premature ejaculation. If both conditions are present, sildenafil may help both problems based on recent studies. Sildenafil in combination with SSRI-type drugs helps premature ejaculation better than SSRI-type medication alone, as measured by prolongation of intravaginal ejaculatory latency time (IELT). More drug-related adverse events may occur because 2 medications are being used (sildenafil and an SSRI) rather than just one.
Adult Dose Starting dose can range from 25-50 mg PO 1-2 h prior to sexual intercourse; best taken on empty stomach; maximum dose is 100 mg
Pediatric Dose Not established
Contraindications Use is contraindicated in patients who are also taking organic nitrates either intermittently or regularly
Interactions Increased levels with CYP3A4 inhibitors (eg, cimetidine, ketoconazole, itraconazole, erythromycin, saquinavir) and protease inhibitors (eg, ritonavir); CYP2C9 inhibitors may decrease sildenafil clearance; CYP3A4 inducers (eg, rifampin) may decrease levels; potentiates hypotensive effects of nitrates; additional supine BP reduction with amlodipine reported; simultaneous administration with alpha-blockers may lead to symptomatic hypotension; sildenafil dose should not exceed 25 mg and should not be taken within 4 h of taking an alpha-blocker (tamsulosin HCL [Flomax] may be an exception, as it is much more specific for prostate receptors than for vascular smooth muscle receptors); avoid with other ED treatments (increased risk of priapism)
Pregnancy B - Usually safe but benefits must outweigh the risks.
Precautions Caution with MI, stroke, or life-threatening arrhythmia within last 6 months; with resting hypotension (BP < 90/50) or hypertension (BP > 170/110); unstable angina due to cardiac failure or CAD; anatomical penile deformation; predisposition to priapism; and retinitis pigmentosa; avoid in men where sexual activity is inadvisable due to underlying cardiovascular status; decrease in supine BP reported
Further Outpatient Care
Outpatient care can be scheduled as appropriate for the clinical circumstances.
In/Out Patient Meds
Premature ejaculation is a nonurgent problem that is treated best in an outpatient setting. Medication can be part of the treatment, and adjustments to medication may be necessary based on patient response. (See Treatment and Medication).
Deterrence/Prevention
Future research might indicate whether the incidence of premature ejaculation in young men can be decreased by better sex education during adolescence. Early successful treatment of erectile dysfunction (ED) possibly prevents secondary premature ejaculation in older men.
Complications
Severe premature ejaculation can cause stress within a marriage or other relationship, which might contribute to conflicts and separation or divorce in some cases. Conception is also difficult in cases of premature ejaculation before vaginal intromission.
Prognosis
Masters and Johnson claim that the great majority of men with premature ejaculation (>85%) can be treated successfully with the squeeze-pause technique alone. In most cases, they claim success is achieved within 3 months of the start of therapy. Although Masters and Johnson reported good results, clinical experience varies widely and some authors have observed much poorer success with the squeeze technique. With a combination of methods, including SSRI-type medications, achieving improvement or cure in most cases should be possible, provided that the couple (not just the man) is committed to working on this problem together. A number of published reports also indicate that counseling and medical therapy can help achieve success rates as high as 85%, certainly equal to that reported originally by Masters and Johnson. The problem with all treatments is that the relapse rate is 20-50%, depending on the study, and thus, the durability of the response can be questionable. Some males may need to make a long-term commitment to periodically repeating the behavioral techniques (long-standing habits can be difficult to modify). Some who succeed with medical therapy (ie, SSRIs) might need to use the medication for the remainder of their lives, just as some people with depression need life-long medication to avoid repeated bouts of depression or many with high blood pressure need life-long antihypertensives to control their blood pressure. The precise long-term failure rates are not well established and depend on the duration of follow-up for a particular cohort of patients.
Patient Education
Medical/Legal Pitfalls
Because premature ejaculation is not a medically dangerous condition, a failure to diagnose or to treat this condition successfully usually does not result in medical/legal problems. Before the availability of several nonsurgical methods for treating erectile dysfunction (ED), a patient, mistakenly diagnosed with ED, might have undergone a penile prosthesis implant that would have yielded unsatisfactory results for the patient because of the incorrect initial diagnosis. Even in this scenario, the patient would climax prematurely, but he would still be able to engage in sexual intercourse because his erection would remain adequate because of the presence of the penile implant. Currently, penile implants are placed much more rarely, and with the use of nonsurgical treatments for ED, any permanent harm resulting from diagnosing ED rather than premature ejaculation is unlikely.
Abdel-Hamid IA. Phosphodiesterase 5 inhibitors in rapid ejaculation: potential use and possible mechanisms of action. Drugs. 2004;64(1):13-26. [Medline]. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th ed. Washington, DC: APA Press; 1994. Assalian P. Guidelines for the pharmacotherapy of premature ejaculation. World J Urol. Jun 2005;23(2):127-9. [Medline]. Balon R. Antidepressants in the treatment of premature ejaculation. J Sex Marital Ther. 1996;22(2):85-96. [Medline]. Berkovitch M, Keresteci AG, Koren G. Efficacy of prilocaine-lidocaine cream in the treatment of premature ejaculation. J Urol. Oct 1995;154(4):1360-1. [Medline]. Brown AJ. Ciprofloxacin as cure of premature ejaculation. J Sex Marital Ther. Oct-Dec 2000;26(4):351-2. [Medline]. Busato W, Galindo CC. Topical anaesthetic use for treating premature ejaculation: a double-blind, randomized, placebo-controlled study. BJU Int. May 2004;93(7):1018-21. [Medline]. Carson C, Glasser D, Laumann E. Prevalence and correlates of premature ejaculation among men aged 40 years and older: a United States nationwide population-based study. Program and abstracts from the American Urological Association 98th Annual Meeting; April 26-May 1, 2003, Chicago, I. Abstracts of the American Urological Association 98th Annual Meeting; April 26-M. Cavallini G. Alpha-1 blockade pharmacotherapy in primitive psychogenic premature ejaculation resistant to psychotherapy. Eur Urol. 1995;28(2):126-30. [Medline]. Chen J, Mabjeesh NJ, Matzkin H, Greenstein A. Efficacy of sildenafil as adjuvant therapy to selective serotonin reuptake inhibitor in alleviating premature ejaculation. Urology. Jan 2003;61(1):197-200. [Medline]. Choi HK, Xin ZC, Choi YD, et al. Safety and efficacy study with various doses of SS-cream in patients with premature ejaculation in a double-blind, randomized, placebo controlled clinical study. Int J Impot Res. Oct 1999;11(5):261-4. [Medline]. Choi HK, Jung GW, Moon KH, et al. Clinical study of SS-cream in patients with lifelong premature ejaculation. Urology. Feb 2000;55(2):257-61. [Medline]. Clayton DO, Shen WW. Psychotropic drug-induced sexual function disorders: diagnosis, incidence and management. Drug Saf. Oct 1998;19(4):299-312. [Medline]. Cohen PG. The association of premature ejaculation and hypogonadotropic hypogonadism. J Sex Marital Ther. Fall 1997;23(3):208-11. [Medline]. Cohen PG, Holbrook JM. Effects of fenfluramine on ejaculatory function, luteinizing hormone and testosterone levels in men with hypogonadotropic hypogonadism and premature ejaculation. Int Clin Psychopharmacol. Mar 1999;14(2):91-4. [Medline]. Colpi GM, Fanciullacci F, Aydos K, Grugnetti C. Effectiveness mechanism of chlomipramine by neurophysiological tests in subjects with true premature ejaculation. Andrologia. Jan-Feb 1991;23(1):45-7. [Medline]. Cooper AJ, Cernovsky ZZ, Colussi K. Some clinical and psychometric characteristics of primary and secondary premature ejaculators. J Sex Marital Ther. Winter 1993;19(4):276-88. [Medline]. Dunn KM, Croft PR, Hackett GI. Association of sexual problems with social, psychological, and physical problems in men and women: a cross sectional population survey. J Epidemiol Community Health. Mar 1999;53(3):144-8. [Medline]. Eledjam JJ, Viel E, Bassoul B, Bruelle P. [Non-analgesic effects of opioids]. Cah Anesthesiol. 1991;39(2):111-4. [Medline]. Epperly TD, Moore KE. Health issues in men: part I: Common genitourinary disorders. Am Fam Physician. Jun 15 2000;61(12):3657-64. [Medline]. Fanciullacci F, Colpi GM, Beretta G, Zanollo A. Cortical evoked potentials in subjects with true premature ejaculation. Andrologia. Jul-Aug 1988;20(4):326-30. [Medline]. Fein RL. Intracavernous medication for treatment of premature ejaculation. Urology. Apr 1990;35(4):301-3. [Medline]. Girgis SM, El-Haggar S, El-Hermouzy S. A double-blind trial of clomipramine in premature ejaculation. Andrologia. Jul-Aug 1982;14(4):364-8. [Medline]. Godpodinoff ML. Premature ejaculation: clinical subgroups and etiology. J Sex Marital Ther. Summer 1989;15(2):130-4. [Medline]. Goldmeier D, Keane FE, Carter P, et al. Prevalence of sexual dysfunction in heterosexual patients attending a central London genitourinary medicine clinic. Int J STD AIDS. May 1997;8(5):303-6. [Medline]. Goodman RE. An assessment of clomipramine (Anafranil) in the treatment of premature ejaculation. J Int Med Res. 1980;8 Suppl 3:53-9. [Medline]. Haensel SM, Rowland DL, Kallan KT. Clomipramine and sexual function in men with premature ejaculation and controls. J Urol. Oct 1996;156(4):1310-5. [Medline]. Hellstrom WJG. Premature Ejaculation: Out of the Dark Ages and Into the 21st Century. Urology Times, Supplement. 2005;33:1-20. Henry R, Morales A. Topical lidocaine-prilocaine spray for the treatment of premature ejaculation: a proof of concept study. Int J Impot Res. Aug 2003;15(4):277-81. [Medline]. Homonnai ZT, Shilon M, Paz GF. Phenoxybenzamine--an effective male contraceptive pill. Contraception. May 1984;29(5):479-91. [Medline]. Hsieh JT, Chang HC, Law HS, et al. In vivo evaluation of serotonergic agents and alpha-adrenergic blockers on premature ejaculation by inhibiting the seminal vesicle pressure response to electrical nerve stimulation. Br J Urol. Aug 1998;82(2):237-40. [Medline]. Hurwitz MB. Sexual dysfunction associated with infertility. A comparison of sexual function during the fertile and the non-fertile phase of the menstrual cycle. S Afr Med J. Jul 15 1989;76(2):58-61. [Medline]. Kara H, Aydin S, Yucel M, et al. The efficacy of fluoxetine in the treatment of premature ejaculation: a double-blind placebo controlled study. J Urol. Nov 1996;156(5):1631-2. [Medline]. Kilic S, Ergin, H, Baydinc YC. Venlafaxine extended release for the treatment of patients with premature ejaculation: a pilot, single-blind, placebo-controlled, fixed-dose crossover study on short-term administration of an antidepressant drug. Int J Androl. 2005;28:47. [Medline]. Kim JJ, Kwak TI, Jeon BG, et al. Effects of glans penis augmentation using hyaluronic acid gel for premature ejaculation. Int J Impot Res. Dec 2004;16(6):547-51. [Medline]. Kim SC, Seo KK. Efficacy and safety of fluoxetine, sertraline and clomipramine in patients with premature ejaculation: a double-blind, placebo controlled study. J Urol. Feb 1998;159(2):425-7. [Medline]. Kim SW, Paick JS. Short-term analysis of the effects of as needed use of sertraline at 5 PM for the treatment of premature ejaculation. Urology. Sep 1999;54(3):544-7. [Medline]. Korenman SG. New insights into erectile dysfunction: a practical approach. Am J Med. Aug 1998;105(2):135-44. [Medline]. Kuhr CS, Heiman J, Cardenas D, et al. Premature emission after spinal cord injury. J Urol. Feb 1995;153(2):429-31. [Medline]. Laumann EO, Paik A, Rosen RC. Sexual dysfunction in the United States: prevalence and predictors. JAMA. Feb 10 1999;281(6):537-44. [Medline]. Laumann EO, Paik A, Rosen RC. The epidemiology of erectile dysfunction: results from the National Health and Social Life Survey. Int J Impot Res. Sep 1999;11 Suppl 1:S60-4. [Medline]. Levine SB. Premature ejaculation: some thoughts about its pathogenesis. J Sex Marital Ther. Summer 1975;1(4):326-34. [Medline]. Masters WH, Johnson VE. Premature ejaculation. In: Human Sexual Inadequacy. Boston, Mass: Little Brown & Company; 1970:. 92-115. McMahon CG. Treatment of premature ejaculation with sertraline hydrochloride. Int J Impot Res. Sep 1998;10(3):181-4; discussion 185. [Medline]. McMahon CG, Touma K. Treatment of premature ejaculation with paroxetine hydrochloride. Int J Impot Res. Oct 1999;11(5):241-245; discussion 246. [Medline]. Metz ME, Pryor JL, Nesvacil LJ, et al. Premature ejaculation: a psychophysiological review. J Sex Marital Ther. Spring 1997;23(1):3-23. [Medline]. Montague DK, Jarow J, Broderick GA, et al. AUA guideline on the pharmacologic management of premature ejaculation. J Urol. Jul 2004;172(1):290-4. [Medline]. Nathan SG. The epidemiology of the DSM-III psychosexual dysfunctions. J Sex Marital Ther. Winter 1986;12(4):267-81. [Medline]. Paick JS, Jeong H, Park MS. Penile sensitivity in men with premature ejaculation. Int J Impot Res. Dec 1998;10(4):247-50. [Medline]. Pirke KM, Kockott G, Aldenhoff J, et al. Pituitary gonadal system function in patients with erectile impotence and premature ejaculation. Arch Sex Behav. Jan 1979;8(1):41-8. [Medline]. Read S, King M, Watson J. Sexual dysfunction in primary medical care: prevalence, characteristics and detection by the general practitioner. J Public Health Med. Dec 1997;19(4):387-91. [Medline]. Rosen RC. Prevalence and risk factors of sexual dysfunction in men and women. Curr Psychiatry Rep. Jun 2000;2(3):189-95. [Medline]. Rowland DL, Haensel SM, Blom JH, Slob AK. Penile sensitivity in men with premature ejaculation and erectile dysfunction. J Sex Marital Ther. Fall 1993;19(3):189-97. [Medline]. Salonia A, Maga T, Colombo R, et al. A prospective study comparing paroxetine alone versus paroxetine plus sildenafil in patients with premature ejaculation. J Urol. Dec 2002;168(6):2486-9. [Medline]. Seftel AD, Althof SE. Rapid ejaculation. In: Sexual Dysfunction in Medicine. Vol 2. 2000: 10-3. Spector IP, Carey MP. Incidence and prevalence of the sexual dysfunctions: a critical review of the empirical literature. Arch Sex Behav. Aug 1990;19(4):389-408. [Medline]. Symonds T, Roblin D, Hart K, Althof S. How does premature ejaculation impact a man s life?. J Sex Marital Ther. Oct-Dec 2003;29(5):361-70. [Medline]. Ventegodt S. [Sexuality and quality of life. Results from the quality of life-study of 4,626 Danes aged 31-33 years born at Rigshospitalet 1959-1961]. Ugeskr Laeger. Jul 22 1996;158(30):4299-304. [Medline]. Verma KK, Khaitan BK, Singh OP. The frequency of sexual dysfunctions in patients attending a sex therapy clinic in north India. Arch Sex Behav. Jun 1998;27(3):309-14. [Medline]. Virag R, Beck-Ardilly L. [Nosology, epidemiology, clinical quantification of erectile dysfunctions]. Rev Med Interne. 1997;18 Suppl 1:10s-13s. [Medline]. Waldinger MD. Lifelong premature ejaculation: from authority-based to evidence-based medicine. BJU Int. 2005;95:191. [Medline]. Waldinger MD, Olivier B. Utility of selective serotonin reuptake inhibitors in premature ejaculation. Curr Opin Investig Drugs. 2004;5:743. [Medline]. Wiederholt I. [Treatment of premature ejaculation with an antiandrogen]. Psychiatr Prax. Aug 1977;4(3):176-80. [Medline]. Xin ZC, Choi YD, Seong DH, Choi HK. Sensory evoked potential and effect of SS-cream in premature ejaculation. Yonsei Med J. Nov 1995;36(5):397-401. [Medline]. Xin ZC, Chung WS, Choi YD, et al. Penile sensitivity in patients with primary premature ejaculation. J Urol. Sep 1996;156(3):979-81. [Medline]. Xin ZC, Choi YD, Rha KH, Choi HK. Somatosensory evoked potentials in patients with primary premature ejaculation. J Urol. Aug 1997;158(2):451-5. [Medline].
Premature Ejaculation excerpt
Article Last Updated: Dec 14, 2005
