Persistent across all settings (with partner and during masturbation).
Absence of nocturnal or early morning erections. c
Psychogenic ED:
Sudden onset.
Situational (e.g., fails with partner, normal with masturbation).
Preserved nocturnal penile tumescence (NPT) and morning erections.
Libido Assessment:
Intact libido: Points toward vascular, neurogenic, or psychogenic etiology.
Decreased libido: Points toward endocrine dysfunction (hypogonadism, hyperprolactinemia) or major depression.
Physical Exam (PE):
Genitourinary: Testicular volume/consistency (small/soft in hypogonadism), palpable penile plaques or curvature (Peyronie disease), secondary sexual characteristics (gynecomastia, loss of axillary/pubic hair).
Confirmatory / Specialized Testing (rarely needed for routine presentations):
Nocturnal Penile Tumescence (NPT) monitoring (Rigiscan): Objective differentiation of psychogenic (normal nocturnal tumescence) vs organic ED (absent tumescence).
Penile Duplex Doppler US: Assesses cavernosal peak systolic velocity and end-diastolic velocity to differentiate arterial insufficiency from veno-occlusive dysfunction.
Pudendal arteriography: Indicated primarily in young pts with pelvic/perineal trauma candidate for vascular revascularization.
Biopsy: Not applicable.
Differential Diagnostics
Peyronie Disease:
Diff by palpable fibrous plaques in the tunica albuginea, painful erections, and abnormal penile curvature during tumescence; basic erectile mechanism initially intact.
Hypogonadism (Primary or Secondary):
Diff by markedly decreased libido preceding erectile failure, testicular atrophy, loss of secondary sex characteristics, confirmed by low morning total testosterone and abnormal LH/FSH.
Hyperprolactinemia:
Diff by loss of libido, galactorrhea, visual field defects (bitemporal hemianopsia from pituitary adenoma), and elevated serum prolactin with suppressed gonadotropins.
Medication-Induced ED:
Diff by clear temporal association between starting offending agent (e.g., SSRI, beta-blocker) and symptom onset; normalizes after drug withdrawal or dose modification.
Premature Ejaculation:
Diff by normal erectile rigidity and tumescence, but uncontrollable ejaculation within <1 minute of vaginal penetration; no true erectile failure.
Psychogenic ED:
Diff by sudden onset, situational failure, and intact nocturnal/morning erections.
Medication review: Switch beta-blockers to ACEi/ARBs or CCBs; switch SSRIs to bupropion.
Psychosexual therapy for psychogenic ED.
Cardiovascular stratification: High-risk cardiac pts (e.g., unstable angina, recent MI < 2 weeks, decompensated HF) require cardiology clearance prior to resuming sexual activity or starting therapies.
First-line Therapy:
Phosphodiesterase-5 Inhibitors (PDE5i): Sildenafil, Tadalafil, Vardenafil, Avanafil. c
Mechanism: Inhibits cGMP degradation -> smooth muscle relaxation in corpus cavernosum -> increased arterial blood inflow.
Absolute Contraindication: Concurrent use with nitrates (nitroglycerin, isosorbide mononitrate) due to severe, fatal hypotension.
Both NO–cGMP–mediated vasodilation
Precaution: Administer with caution or separate dosing by >= 4 hours when co-prescribed with alpha-blockers (e.g., tamsulosin, doxazosin) to prevent orthostatic hypotension.
Testosterone Replacement Therapy (TRT):
Indicated only for documented biochemical hypogonadism (low morning testosterone on >= 2 draws) accompanied by low libido.
Ineffective as monotherapy for ED if baseline testosterone levels are normal.
Second-line Therapy:
Vacuum Erection Device (VED): Non-invasive mechanical pump that draws blood into corpora; constriction band placed at base (must be removed within 30 min). Ideal for pts intolerant or contraindicated for PDE5i (e.g., pts taking chronic nitrates).
Untreated underlying CAD: Failure to evaluate ED as an early surrogate marker of generalized atherosclerosis leads to missed intervention windows for MI and stroke.