Tadalafil is a medication used to treat erectile dysfunction and pulmonary arterial hypertension. Tadalafil blocks the enzyme (phosphodiesterase 5) that promotes breakdown cGMP (Cyclic guanosine monophosphate) which regulates blood flow in the spongy tissue of the penis, causing an erection. The effect requires sexual arousal. The difference between sildenafil and vardenafil is the half life, which is 17,5 hours. The longer half life is responsible for Tadalafil nickname “The Weekend Pill“.
Tadalafil is more selective compared do Sildenafil and Vardenafil. Therefore common side effects are headache, stomach discomfort or pain, indigestion, burping, acid reflux, back pain, muscle ache, flushing, runny nose and hearing loss.
The recommended dose is 5-20mg once a day, up to 24-36 hours before sexual activity. Tadalafil starts to work within 15-20 minutes. May be taken with or without food.