For more than 100 years, premature ejaculation has been considered a clinical syndrome, but the treatment and research of premature ejaculation has been hampered by the varying criteria and lack of uniformity in the definition of premature ejaculation. The American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM) definition of premature ejaculation used to be widely accepted, although not supported by evidence-based medicine. Recently, the International Society for Sexual Medicine (ISSM) Special Committee on the Definition of Premature Ejaculation and the Committee on Guidelines for Premature Ejaculation both released guidelines related to the diagnosis and treatment of premature ejaculation. The full text was published in SexMedicine and the Journal of Sexual Medicine. The guidelines are an update and reassessment of the 2010 guidelines for the diagnosis and treatment of premature ejaculation and were developed by a multidisciplinary group of international experts in the field of sexuality. In addition, the Special Committee on the Definition of Premature Ejaculation provided a uniform definition of premature ejaculation that encompasses both lifelong premature ejaculation and acquired premature ejaculation. The etiology of premature ejaculation has been hypothesized around somatic and neurobiological aspects for the past 20 years. Scientists have proposed many biological factors to explain premature ejaculation, including overly sensitive glans, overly strong cortical representation of the pubic nerves, interference with central serotonin neurotransmission, erectile difficulties and other sexual coexisting disorders, as well as prostatitis, prescription drug withdrawal, recreational drugs, chronic pelvic pain syndrome, and thyroid disease. However, it should be noted that none of the above “causes” have been verified in large-scale studies. The Special Committee on the Definition of Premature Ejaculation agreed that there is a clear distinction between lifelong premature ejaculation and acquired premature ejaculation, and that the two have different demographic characteristics and etiologies. However, they share some degree of definition in terms of the composition of the time from penetration to ejaculation, delayed ejaculation disorder, and the negative consequences associated with premature ejaculation. Therefore, the Special Committee believes that the two have common conceptual components, which led to the development of a unified definition of lifelong premature ejaculation and acquired premature ejaculation. Finally, the committee considered ejaculatory latency of about 3 minutes or less as additional key definitional criteria for acquired premature ejaculation. III. Classification of premature ejaculation Premature ejaculation as a male sexual dysfunction has a unified definition consisting of the following three parts: 1. Repeated or continuous ejaculation after contact with the vagina from the first sexual intercourse in about 1 minute (lifelong premature ejaculation), or ejaculation latency time reduced to 3 minutes or less (acquired premature ejaculation). 2. Delayed ejaculation disorder occurs with all or almost all vaginal penetration. 3. Negative personal outcomes such as apprehension, worry, confusion, or avoidance of sexual intimacy occur. In addition, the committee concluded that the available objective evidence for premature ejaculation is limited to studies on male vaginal intercourse and that there is a lack of sufficient data to objectively define premature ejaculation for oral, anal, and same-sex sex. IV. Prevalence According to the ISSM and DSM 5th edition definition of premature ejaculation according to intravaginal ejaculation latency time (IELT) of about 1 minute, the lifetime prevalence of premature ejaculation would not exceed 4%. V. Mean ejaculatory latency time The median time of IELT is 5.4 minutes according to studies in several countries, but the time may vary from country to country. VI. Assessment of premature ejaculation 1. The committee concluded that there was insufficient evidence for screening or patient detection of premature ejaculation, either in the general population or in a specific population, but recommended screening of patients with erectile dysfunction (ED). 2, Clinicians are recommended to use a series of screening questions and to ask about history of prior drug use and psychosocial conditions. 3. Because patient self-report is a determinant of treatment seeking and satisfaction, self-evaluation of ejaculatory latency time by patients and their partners is recommended when premature ejaculation occurs, and this should be routinely performed in the clinic. 4. The premature ejaculation summary (PEP) and premature ejaculation index (IPE) questionnaires are the better available premature ejaculation questionnaire measures and are particularly suitable for monitoring treatment response. 5. For lifelong premature ejaculation, a physical examination is recommended for most patients. 6. For acquired premature ejaculation, purposeful correlative testing must be performed to assess underlying or associated disorders such as ED, thyroid disease, and prostatitis. VII. Treatment 1. Strong evidence suggests that dapoxetine is safe and effective when given as needed for either acquired or lifelong premature ejaculation, and dapoxetine has been marketed in some countries. There is strong evidence that off-label use of daily doses of selective 5-hydroxytryptamine reuptake inhibitors (SSRIs), such as paroxetine, sertraline, citalopram, fluoxetine, and serotonin-containing tricyclic chlorpromazine, is safe and effective; in addition, on-demand administration of chlorpromazine, paroxetine, and sertraline for acquired or lifelong premature ejaculation is also safe and effective. 3, There is better evidence that off-label use of local anesthetic drugs given on demand is safe and effective for the treatment of lifelong premature ejaculation. 4. Although some evidence suggests that off-label on-demand or daily dose administration of phosphodiesterase 5 inhibitors (PDE5is) is safe and effective in men with normal erectile function who have lifelong premature ejaculation. However, the use of PDE5is not recommended for men with lifelong premature ejaculation with normal erectile function and further evidence-based studies are needed. 5. Tramadol may be an effective option for premature ejaculation treatment, but given its addictive nature and side effects, it should only be considered when other treatments fail. Tramadol should not be used in combination with an SSRI due to the risk of serotonin syndrome and potential fatalities. Further controlled studies are still needed to evaluate the effectiveness and safety of tramadol for the treatment of premature ejaculation. 6, A small amount of evidence suggests that psychological or behavioral interventions are effective. 7. When men with acquired premature ejaculation have a clear sudden psychological cause or lifelong event and the individual or partner can be treated or successfully treated with pharmacological interventions, a combination of pharmacological and psychological/behavioral treatment may be very useful. Similarly, in men with premature ejaculation with ED, combined treatment may be beneficial for the psychosocial aspects of sexual dysfunction. 8. There is reliable evidence to support the use of ED medications for the treatment of premature ejaculation with ED. Combined use of premature ejaculation medication and ED medication for premature ejaculation with ED is not recommended (Level of Evidence IIIc). 9. Selective dorsal penile nerve excision or the use of hyaluronic acid to enlarge the glans may lead to permanent loss of sexual function and is not recommended for the treatment of premature ejaculation. VIII. Feedback on treatment outcome For treatment outcome, a simple and clear and effective question from the Clinical Global Impression Change (CGIC) can be used: “Compared to before treatment, please describe your premature ejaculation problem: very severe; severe; more severe; no change; slightly improved; improved; very good”.