Renal & Urinary

Erectile dysfunction: workup and management

Clinical Overview and When to Suspect Erectile Dysfunction

— Prevalence rises sharply with age: ~5% at age 40, ~15–25% at age 65, >50% by age 70.

— Affects ~30 million US men; underreported due to stigma.

— ED frequently precedes a major cardiovascular event by 2–5 years because the cavernosal artery (1–2 mm) endothelium fails before coronary (3–4 mm) endothelium.

— A new ED diagnosis is an opportunity for ASCVD risk reduction, diabetes screening, and depression assessment.

— Any man ≥40 with cardiovascular risk factors, diabetes, metabolic syndrome, CKD, OSA, or depression.

— Post-pelvic surgery (radical prostatectomy, cystectomy, low anterior resection), post-pelvic radiation.

— New initiation of SSRIs, thiazides, beta-blockers (non-vasodilating), finasteride, or spironolactone.

— Symptoms of hypogonadism: low libido, fatigue, loss of morning erections, gynecomastia, decreased body hair.

— Organic (gradual onset, preserved libido, absent nocturnal/morning erections): vasculogenic, neurogenic, endocrine, drug-induced, anatomic.

— Psychogenic (sudden onset, situational, preserved nocturnal erections, normal with masturbation): performance anxiety, depression, relationship discord.

— Mixed — most common in clinical practice.

Board pearl: A 55-year-old man with new ED and no obvious cause warrants a fasting lipid panel, HbA1c, BP check, and ASCVD risk calculation — treat ED as a cardiovascular early-warning sign before reaching for sildenafil. Counsel that lifestyle change (weight loss, exercise, smoking cessation, Mediterranean diet) independently improves erectile function.

Definition: persistent (>3 months) inability to attain or maintain an erection sufficient for satisfactory sexual performance. ED is a symptom, not a disease — and a sentinel marker of systemic vascular disease.

Epidemiology:

Why it matters on Step 3:

When to suspect / actively screen:

Classification framework — drives workup:

Presentation Patterns and Key History

— Onset (sudden vs gradual), duration, progression, situational vs global.

— Quality: difficulty attaining vs maintaining; loss of rigidity mid-coitus suggests venous leak.

— Nocturnal/early-morning erections present → psychogenic or medication-induced more likely; absent → organic (vasculogenic, neurogenic, endocrine).

— Libido: low libido + ED → think hypogonadism, hyperprolactinemia, depression, or SSRI effect.

— Ejaculatory and orgasmic function (separate domains — patients often conflate).

— Sudden onset, situational, young patient, preserved morning erections → psychogenic.

— Gradual, global, age >50, vascular risk factors → vasculogenic.

— Post-radical prostatectomy → neurogenic (cavernous nerve injury); recovery may take 12–24 months.

— Post-pelvic trauma/fracture, perineal pain, claudication of buttocks → arteriogenic (Leriche-type).

— Low libido + fatigue + decreased shaving frequency → hypogonadism; check 8 AM total testosterone.

— Bitemporal vision changes + galactorrhea + ED → prolactinoma.

— Antihypertensives: thiazides, non-vasodilating beta-blockers (atenolol, metoprolol). Spare: nebivolol, ARBs, ACEi, CCBs.

— Antidepressants: SSRIs, SNRIs, TCAs. Spare: bupropion, mirtazapine.

— Antiandrogens: finasteride, dutasteride, spironolactone, GnRH agonists, ketoconazole, chronic opioids.

— Recreational: alcohol, tobacco, cocaine, anabolic steroids, marijuana.

Step 3 management: Before prescribing a PDE5 inhibitor, swap the offending antihypertensive (e.g., HCTZ → ARB, atenolol → nebivolol) and reassess in 4–6 weeks — often resolves ED without further intervention and saves cost.

Core history elements — the "ED interview":

Pattern recognition:

Medication review (high-yield offenders):

Psychosocial screen: PHQ-9, relationship satisfaction, partner sexual health, history of trauma, performance anxiety.

Validated tools: IIEF-5 (SHIM) — score ≤21 suggests ED; tracks treatment response longitudinally.

Physical Exam Findings and Hemodynamic Assessment

— BP in both arms, BMI, waist circumference, signs of metabolic syndrome.

— Peripheral pulses — diminished femoral pulses with buttock claudication = Leriche syndrome (aortoiliac occlusive disease); classic triad: ED, claudication, absent femoral pulses.

— Carotid bruits, AAA palpation.

— Body habitus: gynecomastia, decreased body/facial hair, soft small testes (<15 mL by Prader orchidometer) → hypogonadism.

— Visual fields by confrontation → bitemporal hemianopsia of pituitary mass.

— Thyroid exam — both hyper- and hypothyroidism cause ED.

— Lower extremity sensation, vibration, proprioception (diabetic/alcoholic neuropathy).

— Bulbocavernosus reflex (S2–S4 integrity): squeeze glans → anal sphincter contraction.

— Anal tone, perineal sensation (cauda equina, spinal cord lesions).

— Cremasteric reflex.

— Penis: Peyronie plaques (palpable dorsal/lateral fibrous plaques causing curvature and pain), phimosis, hypospadias, prior surgical scars.

— Testes: size, consistency, masses, varicocele.

— DRE: prostate size/nodules — relevant before starting testosterone and for BPH-related lower urinary tract symptoms (overlap syndrome).

Key distinction: Peyronie disease presents with penile curvature, pain with erection, and palpable plaque — managed with oral therapy (acute phase), intralesional collagenase clostridium histolyticum (Xiaflex) for stable curvature 30–90°, or surgery. Don't confuse with priapism or fracture.

Board pearl: A patient with ED + bilateral buttock/thigh claudication + absent femoral pulses needs CT angiography of aortoiliac vessels — vascular surgery referral for revascularization may restore erections more effectively than PDE5 inhibitors alone.

General/cardiovascular exam:

Endocrine exam:

Neurologic exam:

Genitourinary exam:

Skin/extremities: acanthosis nigricans, xanthomas, peripheral edema.

Diagnostic Workup — Initial Labs and Targeted Studies

— Fasting glucose or HbA1c — undiagnosed diabetes in ~10% of new ED.

— Fasting lipid panel — drives ASCVD risk calculation and statin decision.

— Morning total testosterone (8–10 AM) — diurnal peak; confirm low values with a repeat morning total T + free T (calculated or equilibrium dialysis) + LH, FSH, SHBG, prolactin.

— TSH — both hypo- and hyperthyroidism cause ED.

— CBC, BMP — screens for anemia, CKD.

— Normal total T: >300 ng/dL (Endocrine Society); equivocal 200–300 → check free T.

— Low T + low/normal LH-FSH → secondary (hypogonadotropic) hypogonadism → check prolactin, iron studies (hemochromatosis), pituitary MRI if prolactin elevated or other pituitary symptoms.

— Low T + high LH-FSH → primary (hypergonadotropic) hypogonadism → check karyotype if young (Klinefelter 47,XXY).

— Elevated prolactin → confirm, then MRI pituitary; treat prolactinoma with cabergoline first-line.

— PSA before starting testosterone (baseline) in men ≥40.

— Ferritin/transferrin saturation if hypogonadism + arthralgia/diabetes/hepatomegaly → hemochromatosis.

— Sleep study if snoring, daytime fatigue, obesity — OSA causes ED and CPAP reverses it.

— HbA1c ≥6.5% → initiate diabetes management.

CCS pearl: Order labs before prescribing PDE5i — finding HbA1c 9.2% redirects management to glycemic control + statin + lifestyle, which itself improves erectile function within 3–6 months.

Recommended baseline labs in every new ED workup (AUA 2018 guideline):

Interpreting testosterone results:

Selective/additional studies based on history:

What you do NOT routinely need: nocturnal penile tumescence testing, duplex ultrasound, cavernosometry, or angiography — reserved for refractory, young, post-traumatic, or medicolegal cases.

Advanced and Confirmatory Studies

— Young patient (<40) with no risk factors.

— Post-pelvic trauma or pelvic fracture.

— Failure of PDE5 inhibitors at maximum dose × ≥4 attempts.

— Medicolegal evaluation (disability claims, post-surgical injury litigation).

— Surgical candidates (penile prosthesis, vascular reconstruction).

— Gold standard for vasculogenic ED differentiation.

— Peak systolic velocity (PSV) <25 cm/s → arterial insufficiency.

— End-diastolic velocity (EDV) >5 cm/s with low resistive index → venous leak / corporal veno-occlusive dysfunction.

— Normal study with rigid erection → likely psychogenic or neurogenic.

— Three or more REM-associated erections of >70% rigidity at base × 10 minutes = normal → supports psychogenic etiology.

— Absent NPT → organic ED.

— Rarely needed clinically; mostly medicolegal.

Board pearl: A 28-year-old man post-pelvic fracture with ED unresponsive to sildenafil is the classic candidate for penile duplex + pelvic angiography — focal traumatic arterial lesions are amenable to microvascular bypass with durable cure, unlike diffuse atherosclerotic disease in older men.

Key distinction: Vasculogenic ED divides into arterial insufficiency (PSV low) vs venous leak (EDV high) — therapeutic implications differ; venous leak responds poorly to PDE5i.

When to escalate beyond basic workup:

Penile Doppler duplex ultrasound (DUS) with intracavernosal vasoactive injection (alprostadil or trimix):

Nocturnal penile tumescence (NPT) — RigiScan:

Dynamic infusion cavernosometry/cavernosography (DICC): quantifies venous leak; for surgical planning only.

Pelvic angiography: for young men post-pelvic trauma being considered for microvascular arterial bypass.

MRI pituitary: for confirmed hyperprolactinemia or secondary hypogonadism without obvious cause.

Bone densitometry (DXA): baseline in men with confirmed hypogonadism before/during testosterone therapy.

First-Line Management Logic and Lifestyle Foundation

— Lifestyle: weight loss (≥5–10% BMI reduction improves IIEF), moderate-vigorous aerobic exercise ≥150 min/week (RCT evidence: improves erectile function), smoking cessation, alcohol moderation, Mediterranean diet.

— Optimize comorbidities: glycemic control (target HbA1c per individualized goal), BP control, lipid management, treat OSA with CPAP.

— Medication swap:

– Thiazide → ARB/ACEi or CCB.

– Atenolol/metoprolol → nebivolol (NO-mediated vasodilation) or carvedilol.

– SSRI → bupropion or mirtazapine; or add bupropion to SSRI; or scheduled drug holidays for short-half-life SSRIs (not fluoxetine).

— Psychotherapy/sex therapy for psychogenic component — CBT, couples therapy.

— Treat hypogonadism (confirmed low T × 2) with testosterone replacement if symptomatic — improves libido and may augment PDE5i response.

— Treat hyperprolactinemia with cabergoline.

— Treat hypothyroidism with levothyroxine.

Step 3 management: A new ED visit should generate at least three orders: a PDE5i trial, a cardiovascular risk reduction plan (statin per ASCVD risk, BP/glycemic optimization), and a follow-up appointment in 4–6 weeks to assess response and titrate. Don't just hand out a prescription.

Step 1 — Address reversible causes first (do not skip, even if prescribing PDE5i):

Step 2 — Replace deficiencies:

Step 3 — Pharmacotherapy with PDE5 inhibitors (next chunk).

Step 4 — Second-line therapies if PDE5i fails or contraindicated: intraurethral alprostadil (MUSE), intracavernosal injection (alprostadil, bimix, trimix), vacuum erection device (VED).

Step 5 — Third-line / surgical: penile prosthesis (inflatable or malleable); penile arterial revascularization in selected young trauma patients.

Pharmacotherapy — PDE5 Inhibitors First-Line

— Sildenafil (Viagra): 50 mg 1 hr before sex (range 25–100 mg); fatty meals delay absorption. T½ ~4 h.

— Vardenafil (Levitra): 10 mg (range 5–20 mg); similar profile to sildenafil.

— Tadalafil (Cialis): 10 mg 30 min–2 hr before sex (range 5–20 mg) OR daily 2.5–5 mg — preferred for frequent activity, also FDA-approved for BPH/LUTS (great two-for-one in older men). T½ ~17.5 h.

— Avanafil (Stendra): 100–200 mg 15–30 min before; most selective, fastest onset.

— Trial adequate dose (often max) on ≥6–8 occasions with proper timing, stimulation, and food considerations before declaring failure.

— Switching agents helps ~50% of initial non-responders.

— Concurrent nitrates (any form, any frequency) → life-threatening hypotension. Must wait 24 h after sildenafil/vardenafil, 48 h after tadalafil before giving nitrates in an emergency (e.g., MI).

— Riociguat (soluble guanylate cyclase stimulator, used in pulmonary hypertension) → severe hypotension.

— Alpha-blockers (tamsulosin, doxazosin) — separate by ≥4 h, start PDE5i at low dose.

— Severe hepatic or renal impairment — dose reduce.

— CYP3A4 inhibitors (ketoconazole, ritonavir, erythromycin) — reduce PDE5i dose.

— Recent stroke (<6 months), MI <6 weeks, unstable angina, NYHA III–IV HF, uncontrolled HTN, hypotension <90/50.

Board pearl: A man on tamsulosin for BPH with ED → daily tadalafil 5 mg treats both conditions.

Mechanism: inhibit PDE5 → cGMP accumulates in corpus cavernosum smooth muscle → vasodilation → erection. Requires intact NO pathway and sexual stimulation (does not cause spontaneous erection).

Agents and dosing:

Counseling on failure:

Contraindications — ABSOLUTE:

Relative cautions:

Adverse effects: headache, flushing, dyspepsia, nasal congestion, myalgia (tadalafil — PDE11 cross-reactivity), transient blue-tinted vision (sildenafil — PDE6), NAION (rare), sudden sensorineural hearing loss (rare — stop drug).

Second- and Third-Line Therapy: Injections, Devices, Prosthesis

— Agents: alprostadil (PGE1) 2.5–60 mcg; bimix (papaverine + phentolamine); trimix (papaverine + phentolamine + alprostadil) — most potent, used when alprostadil alone fails.

— Self-injected into lateral corpus cavernosum 5–20 min before sex.

— Effective in 70–90%, including post-radical prostatectomy and diabetic neuropathy.

— Adverse effects: penile pain (most common with alprostadil), hematoma, priapism (>4 hr → urgent urology), corporal fibrosis with long-term use.

— Contraindicated in sickle cell disease, leukemia/myeloma (priapism risk), patients on anticoagulation (relative).

— Mechanical pump creates negative pressure → engorgement; constriction band at base maintains erection.

— Safe in nearly all patients including those on anticoagulants.

— Side effects: cold/cyanotic erection, ejaculatory discomfort, hinging at base; remove band within 30 min to avoid ischemia.

— Useful for penile rehabilitation post-prostatectomy to preserve length and oxygenation.

— Inflatable (3-piece) — most natural; reservoir, pump in scrotum, paired cylinders.

— Malleable (semirigid) — simpler, less mechanical failure, good in poor manual dexterity.

— Indications: failure of all medical therapy, severe Peyronie with ED, refractory venous leak.

— Risks: infection (1–3%, higher in diabetes), mechanical failure, erosion. Preop HbA1c <8.5% target.

— Patient satisfaction 90%+ but irreversibly destroys native erectile tissue.

Step 3 management: Treat priapism >4 hr as a urologic emergency — aspiration of corporal blood ± intracavernosal phenylephrine is first-line ischemic priapism therapy; consult urology immediately.

Second-line therapies (after PDE5i failure or contraindication):

Intracavernosal injection (ICI):

Intraurethral alprostadil (MUSE): 125–1000 mcg pellet; less effective than ICI; can cause hypotension, urethral burning.

Vacuum erection device (VED):

Third-line — penile prosthesis (definitive):

Penile arterial bypass: young, post-traumatic, focal arterial lesion — niche.

Low-intensity shockwave therapy and PRP: investigational; not standard of care.

Special Populations — Elderly, Renal, and Hepatic Impairment

— ED prevalence >50%; rarely "just aging" — pursue workup with same rigor.

— Polypharmacy review essential — deprescribe offending agents per Beers criteria considerations.

— Cardiovascular fitness for sex: apply Princeton III consensus — patients who can climb 2 flights of stairs (~4 METs) without symptoms are generally safe for intercourse and PDE5i.

— Start PDE5i at lowest dose (sildenafil 25 mg, tadalafil 5 mg PRN) and titrate.

— Higher fall risk with orthostasis if also on alpha-blockers or antihypertensives.

— Assess cognitive capacity and partner status; address concurrent depression.

— ED prevalence ~70% in dialysis patients — multifactorial: vasculopathy, autonomic neuropathy, secondary hypogonadism, anemia, secondary hyperparathyroidism, zinc deficiency, depression.

— PDE5i dosing in CKD:

– CrCl <30: sildenafil start 25 mg; tadalafil PRN max 5 mg, avoid daily dosing; vardenafil start 5 mg.

— Optimize anemia (ESA), correct mineral-bone disease, evaluate for hypogonadism.

— Successful renal transplant frequently restores erectile function — counsel patients pre-transplant.

— Child-Pugh A–B: sildenafil start 25 mg, tadalafil start 5 mg PRN, avoid daily tadalafil in severe disease.

— Avoid vardenafil in severe hepatic impairment.

— Cirrhotic patients often have hypogonadism (decreased SHBG, increased aromatization).

— Stable CAD on standard meds (no nitrates): PDE5i generally safe.

— Absolute no-go: nitrates, NYHA IV HF, recent MI/stroke <2–6 weeks, uncontrolled arrhythmia, severe AS.

— Cardiology clearance for intermediate-risk patients (Princeton III).

Board pearl: A patient on isosorbide mononitrate asks for sildenafil → the answer is never co-administer; transition the patient to nitrate-free regimen for ≥1 week or choose an alternative ED therapy (VED, ICI). Sublingual nitroglycerin for chest pain is contraindicated within 24–48 h of PDE5i — use alternative anti-ischemic therapy acutely.

Elderly (≥65):

Chronic kidney disease:

Hepatic impairment:

Cardiovascular disease:

Special Populations — Post-Prostatectomy, Diabetes, Spinal Cord Injury, Younger Men

— Cavernous nerve injury → neurogenic ED in 30–80% depending on nerve-sparing technique.

— Penile rehabilitation: start early (within weeks) — daily low-dose PDE5i (tadalafil 5 mg daily or sildenafil 50 mg 3×/week), VED, and/or ICI to preserve corporal oxygenation and prevent fibrosis.

— Recovery may take up to 24 months; counsel patiently.

— If PDE5i fails → intracavernosal injections are highly effective in this population.

— ED 3× more prevalent; multifactorial (vasculopathy + autonomic neuropathy + endothelial dysfunction + hypogonadism).

— Less responsive to PDE5i (~50–60% vs 80% in non-diabetics) — often need maximum doses or escalation to ICI.

— Tight glycemic control improves but does not reverse established ED — emphasize prevention.

— Erectile capacity depends on level/completeness — upper motor neuron lesions preserve reflexogenic erections; complete lower lesions impair both reflexogenic and psychogenic.

— PDE5i effective; ICI and VED also options.

— Autonomic dysreflexia risk during sexual activity in lesions above T6.

— More often psychogenic, drug-induced (SSRIs, finasteride, anabolic steroids), or post-traumatic.

— Workup includes thorough psychosocial evaluation, drug history, testosterone (anabolic steroid abuse suppresses HPG axis), and consideration of penile duplex.

— Finasteride-associated sexual dysfunction (post-finasteride syndrome) — counsel before prescribing for hair loss.

Step 3 management: For a man 8 weeks post-nerve-sparing prostatectomy with ED, don't wait for spontaneous recovery — start scheduled PDE5i or VED-based rehabilitation at the first post-op visit; document IIEF-5 to track recovery trajectory.

Post-radical prostatectomy:

Diabetes mellitus:

Spinal cord injury:

Younger men (<40):

Pregnancy/pediatrics: N/A for ED, but adolescents with priapism → workup for sickle cell disease, leukemia, trauma.

Complications and Adverse Outcomes

— Psychosocial: depression, anxiety, relationship breakdown, decreased quality of life, decreased adherence to chronic disease medications (when patients blame the drugs).

— Missed cardiovascular diagnosis: ED as a sentinel symptom — failure to risk-stratify means missed opportunity for MACE prevention.

— Cardiovascular: hypotension (especially with nitrates, alpha-blockers), syncope.

— Ophthalmologic:

– NAION (non-arteritic anterior ischemic optic neuropathy) — sudden painless monocular vision loss, "altitudinal" field defect; stop drug, urgent ophthalmology.

– Cyanopsia (blue tint) — sildenafil > others; benign, transient.

— Otologic: sudden sensorineural hearing loss — stop drug, urgent ENT/audiology.

— Priapism: rare with PDE5i alone; higher risk with combination therapy.

— Priapism (ischemic, >4 hr) — emergency: aspirate corporal blood, irrigate with dilute phenylephrine 100–500 mcg q3–5 min up to 1 mg total, monitor BP/HR; if fails → surgical shunt. Sickle cell or hematologic priapism may need exchange transfusion.

— Corporal fibrosis, plaques with long-term use.

— Penile pain (alprostadil), hematoma, injection-site infection.

— Infection (1–3%, ~5% in diabetes) — frequently requires explant.

— Mechanical failure (5-year survival ~85–90%), erosion through tunica or urethra, autoinflation, "S-shaped" deformity.

— Erythrocytosis (Hct >54% → hold, phlebotomize) — check Hct at 3, 6, 12 months, then yearly.

— Worsened OSA, acne, gynecomastia, infertility (suppresses spermatogenesis — co-administer hCG if fertility desired), accelerated growth of prostate cancer (contraindicated in active prostate ca), possibly increased VTE risk.

— Cardiovascular risk debated — TRAVERSE trial (2023) showed non-inferiority vs placebo for MACE in middle-aged/older men with hypogonadism.

Board pearl: Sudden painless vision loss in a man recently on sildenafil = NAION until proven otherwise — stop the drug.

Complications of untreated ED:

Complications of PDE5 inhibitors:

Complications of intracavernosal injection:

Complications of penile prosthesis:

Complications of testosterone replacement therapy (TRT):

When to Escalate Care — Consult, Refer, or Admit

— Ischemic priapism >4 hours → urology STAT; admit if shunt procedure required.

— Acute NAION or sudden SNHL on PDE5i → stop drug, urgent ophthalmology/ENT, hospital admission if bilateral.

— Hypotension/syncope from PDE5i + nitrate co-ingestion → ED, IV fluids, alpha-agonists if refractory, avoid additional nitrates.

— Penile fracture (audible pop, immediate detumescence, eggplant deformity, often during vigorous intercourse) → urology emergency for surgical repair within 24 h.

— Failure of PDE5i trial at maximum dose × 6–8 attempts after switching agents.

— Anatomic abnormalities — significant Peyronie disease, congenital curvature.

— Suspected venous leak or arteriogenic ED in young/post-trauma patient.

— Candidacy for ICI training, VED prescription, or penile prosthesis.

— Concomitant BPH with severe symptoms requiring procedural intervention.

— Refractory or complex hypogonadism (especially secondary with abnormal MRI).

— Hyperprolactinemia with macroprolactinoma.

— Hemochromatosis-related hypogonadism.

— Intermediate-risk Princeton III patients before resuming sexual activity.

— Patients with unstable CAD, recent MI, NYHA III–IV, severe valvular disease.

— Need for nitrate-free regimen optimization before PDE5i.

— Predominantly psychogenic ED, severe relationship discord, depression with suicidal ideation, history of sexual trauma.

— Suspected aortoiliac occlusive disease (Leriche), abnormal pulses, claudication.

CCS pearl: On a CCS case with ED and chest pain on PDE5i, do not order nitroglycerin — choose morphine, oxygen if hypoxic, aspirin, heparin, and IV fluids; consult cardiology and pursue early cath/PCI as indicated.

Urgent / emergent (ED-related):

Urology referral (outpatient):

Endocrinology referral:

Cardiology referral:

Mental health referral:

Vascular surgery referral:

Key Differentials — Within the Sexual Dysfunction Spectrum

— Patient describes lack of interest rather than failure of erection.

— Causes: hypogonadism, hyperprolactinemia, depression, SSRIs, relationship issues, chronic illness.

— Workup: testosterone, prolactin, TSH, depression screen.

— Treatment: treat cause; flibanserin/bremelanotide are FDA-approved for women, not men.

— Ejaculation within ~1 minute of penetration with distress (lifelong) or significant reduction in latency (acquired).

— First-line: behavioral techniques (stop-start, squeeze), topical lidocaine-prilocaine cream, SSRIs (paroxetine, sertraline; dapoxetine where available), on-demand or daily.

— May coexist with ED — treat ED first.

— Causes: SSRIs (most common), antipsychotics, opioids, alpha-blockers (paradoxically), aging, neuropathy.

— Switch offending drug; trial bupropion.

— Orgasm with dry ejaculate and cloudy first-void urine (sperm in urine).

— Causes: tamsulosin/silodosin, prior TURP, diabetes, retroperitoneal lymph node dissection.

— Treatment: stop offending alpha-blocker; pseudoephedrine or imipramine for fertility; sperm retrieval from urine for assisted reproduction.

— Inability to reach orgasm despite adequate erection and stimulation.

— Causes: SSRIs, opioids, neurologic disease.

— Curvature + pain + plaque; may coexist with ED.

Key distinction: A man on tamsulosin with "no ejaculate" doesn't have ED — he has retrograde ejaculation; reassure, switch to non-alpha-blocker (5-ARI, mirabegron alternative is not applicable), or accept the trade-off if BPH symptoms well-controlled.

ED must be distinguished from other male sexual dysfunctions — each has different workup and treatment:

Low libido (hypoactive sexual desire disorder):

Premature ejaculation (PE):

Delayed/absent ejaculation:

Retrograde ejaculation:

Anorgasmia:

Peyronie disease:

Key Differentials — Other-Category Mimics and Coexisting Conditions

— Low libido predominates; erections may be partially preserved with sufficient stimulation.

— Confirmed by two morning total T <300 ng/dL with symptoms; treat with TRT.

— May present as ED or be the cause; SSRIs used to treat depression then worsen ED — vicious cycle.

— Use PHQ-9, GAD-7; consider bupropion as antidepressant of choice when sexual dysfunction is a concern.

— ED + low libido + galactorrhea + bitemporal hemianopsia + headache.

— Confirmed by elevated prolactin → MRI pituitary → cabergoline first-line.

— Either can cause ED; correct thyroid status.

— ED from secondary hypogonadism via pituitary iron deposition; check ferritin/transferrin saturation.

— Hypoxia and sleep fragmentation impair endothelial function and testosterone; CPAP improves ED.

— Each contributes via multiple mechanisms; address the systemic disease.

— Neurogenic ED; abnormal bulbocavernosus reflex or sacral signs help localize.

Board pearl: A 35-year-old bodybuilder with ED, low libido, small soft testes, low LH/FSH, and normal/high estradiol — think exogenous anabolic steroid use suppressing HPG axis; recovery may take months after cessation, and clomiphene or hCG + recombinant FSH can restore endogenous function/fertility.

Conditions that mimic or coexist with ED:

Hypogonadism alone:

Depression and anxiety:

Hyperprolactinemia / pituitary adenoma:

Hypo/hyperthyroidism:

Cushing syndrome and chronic glucocorticoid use: suppress HPG axis.

Hemochromatosis:

Obstructive sleep apnea:

Chronic kidney disease, cirrhosis, COPD, heart failure:

Multiple sclerosis, Parkinson disease, stroke, spinal cord lesions, diabetic autonomic neuropathy:

Peripheral vascular disease, aortoiliac disease: vasculogenic ED.

Substance use: chronic alcohol, opioids, marijuana, cocaine, methamphetamine, anabolic steroids.

Secondary Prevention and Long-Term Plan

— Calculate 10-year ASCVD risk; initiate statin per current guidelines (moderate-intensity if 7.5–19.9%, high-intensity if ≥20% or established ASCVD).

— BP target generally <130/80 per ACC/AHA in patients with ASCVD risk ≥10%.

— Diabetes: individualized HbA1c (often <7%); prefer SGLT2i/GLP-1RA in patients with established ASCVD or CKD.

— Aspirin only for established ASCVD (not primary prevention in most patients).

— Aerobic exercise ≥150 min/week moderate or 75 min vigorous + resistance training 2×/week.

— Mediterranean diet — independently improves IIEF.

— Weight loss ≥5–10%, smoking cessation, alcohol ≤2 drinks/day, sleep hygiene.

— Treat depression, anxiety; bupropion-preferred SSRI alternative; consider couples therapy.

— Daily low-dose tadalafil for men with frequent activity or coexisting BPH.

— Reassess offending drugs at every visit.

— Monitor symptom response (libido, energy, mood, IIEF).

— Labs: total T at 3, 6, 12 months then yearly (target mid-normal range).

— Hct at 3, 6, 12 months then yearly — hold if Hct >54%.

— PSA + DRE at baseline, 3–6 months, then yearly; refer urology if PSA rises >1.4 ng/mL in a year or >0.4 in stable men.

— Bone density at baseline if at risk; reassess in 1–2 years.

— Discuss fertility — TRT suppresses spermatogenesis; use hCG ± FSH if fertility desired.

Step 3 management: Don't let a stable ED patient go without a yearly cardiometabolic checkup — recheck BP, lipids, HbA1c, weight, depression screen, medication review, IIEF-5 annually; uptitrate or modify ED therapy as comorbidities evolve.

Cardiovascular risk reduction (the most important long-term move):

Lifestyle prescription (durable benefit for erectile function):

Mental health and relationships:

Medication maintenance:

Hypogonadism long-term care (if on TRT):

Follow-Up, Monitoring Parameters, and Counseling

— 4–6 weeks after initiating PDE5i — assess efficacy, tolerability, dose adjustment, and address mistimed use (most common reason for "failure").

— 3 months to evaluate sustained response, cardiovascular tolerance, partner satisfaction; consider switching agent if inadequate.

— 6–12 months for routine reassessment, comorbidity optimization, IIEF-5 score.

— Sooner if adverse effects or new cardiovascular symptoms.

— Office training visit for technique.

— Follow-up at 1 month — assess priapism episodes, hematomas, pain.

— Periodic palpation for corporal plaques/fibrosis.

— Wound check at 2 weeks; device activation at 4–6 weeks.

— Annual urology follow-up for mechanical function.

— PDE5i requires sexual stimulation — it doesn't create erections out of nothing.

— Take adequately in advance — sildenafil 60 min before, tadalafil 30 min–2 h before; avoid heavy fatty meals (sildenafil/vardenafil).

— Allow adequate attempts before declaring failure (≥6–8 at max dose).

— Realistic expectations: ~70–80% success in non-diabetic, ~50% in diabetic ED.

— Never combine with nitrates or recreational "poppers" (amyl nitrite) — life-threatening.

— Sex is "exercise" — counsel cardiac patients about Princeton III risk stratification.

— Discuss partner involvement in treatment decisions when appropriate.

— Discuss STI risk if returning to sexual activity after long abstinence — particularly older men, where syphilis and HIV rates are rising.

CCS pearl: On a CCS case for a man with new ED, advance the clock and schedule follow-up labs and a 6-week reassessment visit — both actions earn management points and reflect real practice.

Follow-up cadence after starting therapy:

Monitoring on TRT: (as above) — symptoms, total T, Hct, PSA, lipid profile, fertility status.

Monitoring after ICI initiation:

Penile prosthesis follow-up:

Counseling key points (Step 3 favorites):

Ethical, Legal, and Patient Safety Considerations

— Discuss all therapy tiers (lifestyle, PDE5i, ICI, VED, prosthesis) with realistic success rates, costs, irreversibility (prosthesis destroys native erectile tissue), and adverse effects.

— For TRT, explicitly discuss infertility, erythrocytosis, prostate effects, and cardiovascular uncertainty.

— Document discussions — high medicolegal exposure for sexual medicine, especially prosthesis cases.

— Patients with cognitive impairment in long-term care — assess decision-making capacity for sexual activity; involve ethics/social work when consent is questioned.

— Avoid coercive prescribing on behalf of a partner without patient's own goal alignment.

— Sexual health is sensitive; ensure private visits without partner present for at least part of the encounter to screen for intimate partner violence, hidden substance use, or non-disclosed sexual orientation/practice.

— HIPAA applies — be careful about voicemails, portal messages titled "erectile dysfunction."

— Verify no nitrate use at every PDE5i refill, including OTC chest pain rubs and recreational amyl nitrite ("poppers"). Black-box-level safety issue.

— Screen for counterfeit online pharmacies — unsafe doses, contamination; counsel patients to use legitimate pharmacies.

— Beware of drug interactions — alpha-blockers, CYP3A4 inhibitors, antiretrovirals.

— If ED workup reveals interpersonal violence, comply with state-specific reporting laws; offer resources.

— Disclose any suicidal ideation discovered during depression screen and arrange same-day evaluation.

— A patient discharged after MI with new isosorbide mononitrate must be counseled to stop all PDE5i — verify at discharge med rec; communicate explicitly with PCP, urologist, and pharmacy.

Board pearl: Discharge counseling for a post-MI patient on nitrates must include "no sildenafil/tadalafil/vardenafil/avanafil — ever, in any form, while on this medication" — and the order should be documented.

Informed consent and shared decision-making:

Capacity and partner considerations:

Confidentiality:

Prescription safety:

Mandatory reporting / safety nets:

Transition-of-care risk (classic Step 3 trap):

Equity: PDE5i and prostheses are often poorly covered; advocate generic sildenafil/tadalafil and patient assistance programs to avoid disparities.

High-Yield Associations and Rapid-Fire Clinical Facts

Key distinction: Psychogenic ED = sudden, situational, preserved nocturnal/morning erections; organic ED = gradual, global, absent NPT.

ED + buttock claudication + absent femoral pulses → Leriche syndrome (aortoiliac occlusive disease) → CT angiography → vascular revascularization.

ED + bitemporal hemianopsia + galactorrhea → prolactinoma → MRI pituitary → cabergoline.

ED + bronze skin + diabetes + arthralgias + hepatomegaly → hereditary hemochromatosis → ferritin/Tsat → HFE gene → therapeutic phlebotomy.

ED + small soft testes + tall stature + gynecomastia + learning issues → Klinefelter (47,XXY) → karyotype, TRT.

ED + sudden vision loss on sildenafil → NAION → stop drug.

ED + sudden hearing loss on PDE5i → sudden SNHL → stop drug, urgent steroids per ENT.

ED + chest pain after sildenafil → NEVER nitrates for 24 h (48 h tadalafil) — use alpha-agonists, IV fluids, morphine, PCI as needed.

Painful erection >4 h → ischemic priapism → aspirate + phenylephrine.

ED + dorsal penile plaque + curvature → Peyronie disease → collagenase or surgery.

ED post-radical prostatectomy → penile rehabilitation with daily PDE5i + VED; if fails → ICI.

ED + BPH/LUTS → daily tadalafil 5 mg (treats both).

ED + HFrEF on isosorbide + hydralazine → VED or ICI, not PDE5i.

Dry orgasm + cloudy urine post-orgasm → retrograde ejaculation (often tamsulosin or post-TURP/RPLND).

Bodybuilder + ED + low LH/FSH + low T → anabolic steroid use.

Princeton III rule of thumb: climbing 2 flights of stairs without symptoms = safe for sex/PDE5i.

Hold TRT if Hct >54%; recheck PSA periodically.

First-line for premature ejaculation: SSRI (paroxetine) or topical anesthetic.

PDE5i contraindicated with: nitrates, riociguat.

CYP3A4 inhibitors (ritonavir, ketoconazole): reduce PDE5i dose.

Tadalafil T½ ~17.5 h — "weekend pill."

Board Question Stem Patterns

Step 3 management: When the stem gives you a med list with nitrates and a request for ED treatment, the answer is not PDE5i — pick VED or ICI every time.

Pattern 1 — "Sentinel CV event": 56-year-old man with new ED, fasting glucose 132, BP 148/92, LDL 168. Best next step: initiate ASCVD risk-based therapy (statin, BP control, lifestyle) AND prescribe sildenafil — not just sildenafil.

Pattern 2 — Nitrate co-administration: Man on PDE5i presents with chest pain. Wrong: nitroglycerin. Right: morphine, ASA, heparin, oxygen if hypoxic, PCI.

Pattern 3 — Drug-induced ED: Man started on HCTZ or atenolol or paroxetine, develops ED. Best next step: swap to ARB/CCB, nebivolol, or bupropion before adding PDE5i.

Pattern 4 — Hypogonadism workup: Man with ED, low libido, fatigue. Total T 220 ng/dL. Best next step: repeat morning total T + free T, LH/FSH, prolactin, TSH — confirm before treating.

Pattern 5 — Hyperprolactinemia: ED, headaches, bitemporal hemianopsia, low T, prolactin 350. Diagnosis: prolactinoma. Treatment: cabergoline; MRI to confirm.

Pattern 6 — Post-prostatectomy: 8 weeks post nerve-sparing radical prostatectomy, no erections. Best next step: initiate penile rehabilitation with daily low-dose PDE5i ± VED; reassess at 6–12 months; if fails, ICI.

Pattern 7 — Leriche: Buttock claudication + absent femoral pulses + ED. Diagnosis: aortoiliac occlusive disease. Next: ABI + CTA aorta/iliacs; vascular surgery.

Pattern 8 — Priapism: Man on trimix presents with painful 6-hour erection. First step: aspirate corporal blood + intracavernosal phenylephrine.

Pattern 9 — Princeton risk: Man post-MI 4 weeks ago asks to resume sex. Best step: stress test for risk stratification; ensure not on nitrates before PDE5i.

Pattern 10 — Retrograde ejaculation: Man on tamsulosin reports "dry orgasm." Diagnosis: retrograde ejaculation; confirm with post-orgasm urinalysis; counsel and consider switching agent.

Pattern 11 — TRT monitoring: Man on TRT × 6 months — Hct 56%. Next step: hold testosterone; therapeutic phlebotomy.

One-Line Recap

Erectile dysfunction is a symptom of systemic vasculopathy and a sentinel marker for cardiovascular disease — work it up with targeted history (onset, libido, nocturnal erections, medications), baseline labs (HbA1c, lipids, morning testosterone, TSH, prolactin), treat reversible causes and comorbidities first, and offer tiered therapy starting with lifestyle and PDE5 inhibitors, escalating to vacuum devices, intracavernosal injections, and penile prosthesis — while never co-administering with nitrates or riociguat.

Board pearl: The exam-favorite answer to "what's the best next step" in an ED stem is rarely "prescribe sildenafil" — it's almost always identify and modify the underlying contributor first (drug swap, glycemic/BP/lipid control, hypogonadism correction, nitrate avoidance), with PDE5i added as part of a comprehensive plan and reassessed at 4–6 weeks.

Workup essentials: HbA1c, fasting lipids, morning total testosterone, TSH, prolactin, BP — calculate ASCVD risk; medication review for offenders.

First-line therapy: lifestyle + cardiometabolic optimization + PDE5 inhibitor; daily tadalafil 5 mg if BPH coexists; allow 6–8 adequate-dose trials before switching agents.

Escalation ladder: PDE5i → vacuum device or intracavernosal alprostadil/trimix → penile prosthesis; pursue penile rehabilitation post-prostatectomy with early daily PDE5i + VED.

Hard "never" rules: no PDE5i with nitrates or riociguat (24 h washout sildenafil/vardenafil, 48 h tadalafil); hold testosterone if Hct >54%; treat priapism >4 h as emergency with aspiration + intracavernosal phenylephrine.

Don't miss the systemic clue: new ED in a middle-aged man should trigger ASCVD risk reduction, diabetes screening, OSA evaluation, and depression screening — sometimes the most therapeutic prescription is a statin, CPAP, or bupropion rather than sildenafil.