Impotence,Erectile dysfunction

Impotence (Erectile Dysfunction – ED)

Erectile dysfunction (ED), commonly known as impotence, is the persistent inability to achieve or maintain an erection sufficient for satisfactory sexual performance. It is a highly prevalent condition that affects physical, psychological, and social well-being.

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Causes

Erectile dysfunction may arise from physical, psychological, or mixed factors:

Physical causes:

• Cardiovascular disease (atherosclerosis, hypertension, hyperlipidemia)

• Diabetes mellitus (damaging blood vessels and nerves)

• Hormonal imbalances (low testosterone, thyroid disorders, high prolactin)

• Neurological disorders (multiple sclerosis, Parkinson’s disease, spinal cord injury)

• Pelvic surgery or trauma (e.g., prostatectomy)

• Medications (antihypertensives, antidepressants, antipsychotics, antiandrogens, opioids)

• Smoking, alcohol misuse, or substance abuse

Psychological causes:

• Stress, anxiety, depression

• Relationship problems

• Performance anxiety

Mixed causes:

• Common in men with chronic illness where both organic and psychological components coexist

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Diagnosis

• History and examination: medical history, lifestyle, sexual history, physical exam

• Laboratory investigations: fasting glucose, HbA1c, lipid profile, testosterone levels, thyroid function tests

• Specialized tests (if needed): penile Doppler ultrasound, nocturnal penile tumescence test, psychological evaluation

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Treatment

Lifestyle modifications:

• Stop smoking

• Limit alcohol

• Regular exercise

• Weight loss if overweight

• Manage stress and improve sleep quality

Psychological therapy:

• Cognitive-behavioral therapy (CBT)

• Sex therapy

• Couples counseling

Pharmacological treatment:

1. Phosphodiesterase type-5 inhibitors (PDE5 inhibitors):

   • Sildenafil (Viagra) – 25–100 mg taken 30–60 minutes before sexual activity

   • Tadalafil (Cialis) – 5–20 mg, effective up to 36 hours, or 2.5–5 mg daily dose

   • Vardenafil (Levitra) – 5–20 mg before intercourse

   • Avanafil (Stendra) – 50–200 mg before intercourse

   Contraindicated with nitrates and certain antihypertensives due to risk of severe hypotension.

2. Hormone therapy:

   • Testosterone replacement (gel, injection, patch) if hypogonadism confirmed

3. Other oral or injectable drugs:

   • Alprostadil (intracavernosal injection or intraurethral suppository)

   • Papaverine + phentolamine + alprostadil (Trimix injection, specialist use)

Mechanical and surgical options:

• Vacuum erection devices

• Penile prostheses (inflatable or semi-rigid implants)

• Vascular surgery in select cases (rare)

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Contraindications

• PDE5 inhibitors contraindicated with nitrates, guanylate cyclase stimulators (riociguat)

• Uncontrolled cardiovascular disease (unstable angina, recent myocardial infarction or stroke)

• Severe hypotension or uncontrolled hypertension

• Severe liver impairment (dose adjustments needed for some drugs)

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Side Effects of Treatments

• PDE5 inhibitors: headache, flushing, nasal congestion, dyspepsia, visual disturbances, dizziness

• Alprostadil injections: penile pain, prolonged erection (priapism), fibrosis at injection site

• Testosterone replacement: polycythemia, prostate enlargement, risk of prostate cancer progression, sleep apnea exacerbation

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Precautions

• Screen for underlying cardiovascular disease before prescribing ED treatment

• Monitor testosterone, hematocrit, and PSA if on testosterone replacement

• Caution in elderly patients and those with multiple comorbidities

• Ensure psychological support when psychogenic ED is suspected

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Drug Interactions

• PDE5 inhibitors interact with:

• Nitrates (nitroglycerin, isosorbide dinitrate/mononitrate) → life-threatening hypotension

• Alpha-blockers (e.g., doxazosin, tamsulosin) → additive hypotensive effect

• CYP3A4 inhibitors (ketoconazole, ritonavir, erythromycin, clarithromycin, grapefruit juice) → increased PDE5 inhibitor levels

• CYP3A4 inducers (rifampicin, carbamazepine, phenytoin, St. John’s wort) → reduced efficacy