Erectile Dysfunction
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Direct answer
Erection depends on paracrine nitric oxide, cavernosal smooth-muscle relaxation and rapid arterial inflow — which is why the penis works as an early barometer of the vascular tree, erectile dysfunction commonly preceding coronary disease by two to five years. Organic dysfunction arrives gradually, abolishes night and early-morning erections, and travels with diabetes (India's leading organic cause), smoking, hypertension and dyslipidaemia; psychogenic dysfunction is sudden, situational, and preserves nocturnal tumescence. First-line therapy is a phosphodiesterase-5 inhibitor — sildenafil 50 mg an hour before activity, or tadalafil with its long half-life and daily low-dose option — absolutely contraindicated with nitrates. Second-line intracavernosal alprostadil and third-line penile prostheses complete the ladder, with testosterone reserved for proven hypogonadism.
What you must remember
- Organic versus psychogenic: preserved morning erections, sudden onset and situational failure (partner-specific, normal masturbation) point to psychogenic; gradual, progressive loss of all erections with vascular risk factors points to organic — the bedside sorting that saves a battery of tests.
- The vascular equation: erectile dysfunction shares every risk factor with coronary disease; a man under fifty with new dysfunction deserves blood pressure, fasting glucose and lipid measurement — the "penile stress test" framing worth quoting in vivas.
- Drug causes: thiazides, beta-blockers, spironolactone, SSRIs, antipsychotics, 5-alpha-reductase inhibitors, alcohol and opioids — reconcile the list before labelling the patient.
- PDE5 inhibitors: sildenafil 50 mg about an hour before activity (effective four to six hours), tadalafil effective up to 36 hours with a 5 mg daily-dosing option; sexual stimulation is required — they are not aphrodisiacs.
- The nitrate rule: nitrates (GTN, isosorbide) with a PDE5 inhibitor cause life-threatening hypotension — the single most examined fact; separate dosing from alpha-blockers, and treat accidental overlap with the patient supine.
- Second and third lines: intracavernosal alprostadil (prostaglandin E1) is the most effective non-oral option, with priapism and penile fibrosis as warnings; intraurethral alprostadil, vacuum devices, and finally malleable or inflatable penile prostheses for refractory cases.
- Hormonal workup: morning total testosterone, with prolactin, LH and FSH if low; hyperprolactinaemia (low libido, galactorrhoea) is treated with cabergoline or by treating the prolactinoma; testosterone is replaced only when hypogonadism is proven.
- Indian caution: unregulated "herbal" aphrodisiacs sold online and over counters are frequently adulterated with undeclared sildenafil — a real source of nitrate interactions in men who never mentioned taking "medicine".
The diabetic man who finally asks
A 52-year-old with ten years of type 2 diabetes mentions, at the door, difficulty with erections for two years. The sequence: score the severity with the five-item IIEF questionnaire; take the psychogenic history (morning erections preserved? sudden or gradual?); examine the penis for Peyronie's plaques and the testes, check the femoral pulses; test fasting glucose, HbA1c, lipids and a morning testosterone. His cardiovascular risk is the reason the consultation matters — new dysfunction in a diabetic is a prompt to retinopathy and nephropathy screening too, since microvascular disease travels together.
Then treatment: sildenafil 50 mg with instructions that matter more than the prescription — take it on an empty stomach an hour before, with stimulation, and try at least four to six attempts before judging failure. Review the antihypertensive list (swap a thiazide where feasible), reinforce smoking cessation and exercise, and involve the partner in counselling. If PDE5 inhibitors fail with adequate trials, intracavernosal alprostadil 5-10 micrograms taught in clinic is next; the motivated man with a supportive partner can be considered for an inflatable prosthesis, with infection and erosion risks explained honestly.
The one contraindication the exam loves
NBE tests the nitrate-PDE5 interaction from every angle: the man on isosorbide mononitrate asking for sildenafil (refuse), the man who took sildenafil this morning and now has crushing chest pain (nitrates contraindicated — treat with oxygen, aspirin and alternative agents, supine positioning), and the drug-safety one-liner about which class is absolutely contraindicated. The second tier of questions is psychogenic clues, the tadalafil daily-dosing option, and the sequence of therapy — PDE5 inhibitor, then alprostadil, then prosthesis. The vascular pearl (dysfunction preceding coronary events by a few years) earns the distinction between an answer and a rounded answer.
Frequently asked questions
Why are nitrates absolutely contraindicated with PDE5 inhibitors?
Both dilate vessels through the nitric oxide pathway; together they cause profound, refractory hypotension that can be fatal.
Which features suggest psychogenic rather than organic dysfunction?
Sudden onset, situational (partner- or stress-specific), and preserved early-morning erections — organic disease abolishes nocturnal tumescence gradually.
Which PDE5 inhibitor suits daily dosing?
Tadalafil, whose long half-life allows a 5 mg daily regimen and effectiveness up to 36 hours after dosing.
What is second-line therapy after PDE5 inhibitor failure?
Intracavernosal alprostadil (prostaglandin E1), the most effective non-oral option, with priapism counselled as the key risk.
When is testosterone therapy appropriate?
Only for proven hypogonadism on morning testosterone testing with symptoms — never as a nonspecific tonic for erectile complaints.