4 known interactions • 0 major • 3 moderate • 1 minor
Always disclose all medications to your healthcare providers — prescription medicines, OTC medications, vitamins, and herbal supplements. This list may not include every possible interaction. Use our Medicine Interaction Checker to screen your complete medication list.
Potentially life-threatening or causing permanent damage. Avoid combination.
May worsen condition or require dose adjustment. Monitor closely.
Usually limited clinical effect. Manage with routine monitoring.
PDE5 inhibitors (sildenafil, tadalafil, vardenafil)
Additive hypotension. Tamsulosin is the safest alpha-blocker to combine with PDE5 inhibitors (most alpha-1A selective), but symptomatic hypotension still possible.
Management: Use lowest PDE5 inhibitor dose; monitor blood pressure. Tamsulosin-sildenafil combination is better tolerated than doxazosin-sildenafil.
Strong CYP3A4 inhibitors (ketoconazole, ritonavir)
Increase tamsulosin plasma levels significantly.
Management: Avoid combination with potent CYP3A4 inhibitors.
Other alpha-blockers
Additive alpha blockade — increased hypotension risk.
Management: Avoid concomitant use of alpha-blockers.
Antihypertensives
Additive hypotensive effects possible.
Always ask your pharmacist about potential interactions with food, alcohol, and supplements specific to Tamsulosin. Some medicines have significant interactions with grapefruit juice, high-fat meals, dairy products, or vitamin K-rich foods.