- Clinical science
Erectile dysfunction is the most common presentation of sexual dysfunction in males and is characterized by an inability to maintain an adequate erection for sexual intercourse that lasts at least 6 months. The causes may be psychological, vascular, neurological, or hormonal. Diagnosis is made based on a detailed medical history and physical exam, relevant blood tests (e.g., testosterone, sexual hormone-binding globulin), and objective measurement of the remaining erectile function (nocturnal penile tumescence testing). Treatment includes counseling and, in cases with an organic cause, potentially mechanical vacuum pump therapy, medical therapy with phosphodiesterase-5 inhibitors, or surgery (penile prosthesis implant).
Premature ejaculation is characterized by an inability to delay ejaculation during penetration and is often accompanied by significant psychological distress. Proposed etiologies include penile hypersensitivity and psychological disorders such as depression and anxiety. The diagnosis is made with a medical history of short ejaculation latency time, inability to delay or control ejaculation, and psychological strain. Treatment consists of SSRIs and local topical anesthetics with sex therapy and other psychotherapy as needed.
- Erectile dysfunction (): inability to achieve or sustain an erection sufficient in rigidity or duration for sexual intercourse which is present for a minimum of ∼ 6 months 
- See “ ” and “ .”
- Most common sexual disorder in men
Organic (most common)
- Vascular: hypertension, diabetes mellitus, cardiovascular disease, hyperlipidemia, smoking
- Neurogenic: stroke, brain or spinal cord injury, dementia, Parkinson disease, multiple sclerosis
- Endocrine: hypogonadism, hyperprolactinemia, thyroid disorders
- Antihypertensives; (beta-blockers, thiazide diuretics)
- Antidepressants (SSRIs)
- Dopamine antagonists (e.g., antipsychotics): increased prolactin secretion (anterior pituitary) → decreased GnRH secretion (hypothalamus) → decreased LH secretion (anterior pituitary) → decreased testosterone production (Leydig cells) →
- Iatrogenic: surgery or radiotherapy (radical prostatectomy, pelvic radiation)
- Trauma: pelvic fracture and urethral injury
- Alcohol abuse
- Peyronie disease
- Psychogenic: depression, anxiety (performance-related), relationship issues, trauma from prior experiences, stress
- Mixed organic and psychogenic
- Largely a clinical diagnosis
- Detailed patient history and clinical exam
|Diagnostic criteria (according to DSM V)|
- Further tests to exclude organic disorders 
- Endocrinological laboratory analysis: ↓ testosterone, ↑ SHBG, ↑ prolactin, ↓ LH, ↓ FSH, ↑ TSH, ↑ fasting glucose or hemoglobin A1C, abnormal lipid profile
Nocturnal penile tumescence measurement (phallography): measurement of spontaneous nightly erections in erectile dysfunction (primarily performed in a sleep laboratory) to differentiate between organic from psychogenic erectile dysfunction.
- Lack of nocturnal erections suggests an organic etiology (neurogenic or vascular)
- Normal testing suggests a psychogenic etiology
- Duplex Doppler ultrasound or arteriography to identify suspected arterial inflow or venous leaks after injection of vasodilatory agent
Ii is important to identify the underlying etiology to manage lifestyle risk factors and initiate appropriate therapy.
- Sensate focus exercises for performance anxiety
- Group psychotherapy
- Phosphodiesterase-5 inhibitors are considered the only first-line therapy: tadalafil, sildenafil, vardenafil.
- Testosterone replacement if patient's serum testosterone is low (e.g., in hypogonadism)
- Intracavernous injection therapy or prostaglandin E1 (alprostadil) are second-line therapies if PDE-5 inhibitors are ineffective.
- Epidemiology 
Etiology: largely unknown
- Psychogenic factors: depression/anxiety, relationship problems, irregular sexual intercourse
- Organic factors: penile hypersensitivity, hyperexcitability of the reflex arc
|Diagnostic criteria (according to DSM V)|
- The indication primarily depends on the psychological strain on the affected individual.
- Psychotherapy/behavioral therapy
- Medical therapy
- Epidemiology: Incidence increases with age ≥ 50 years. 
- Etiology: psychological stress (e.g., childhood abuse, sexual trauma)
- Diagnosis 
|Diagnostic criteria of delayed ejaculation (DSM V)|
- Other types of therapy depending on the underlying cause of psychological stress
- Definition: fibroproliferative disorder that affects the tunica albuginea of the penis, causing abnormal curvature of the penis
- Pathogenesis: repeated penile microtrauma during sexual intercourse or athletic activity followed by abnormal wound healing → fibrous plaque formation 
- Clinical features
- Differential diagnosis
- First-line: oral pentoxifylline
- Second-line: intralesional collagenase injections
- Third-line: surgical repair