Tadalafil is a phosphodiesterase type 5 (PDE5) inhibitor. It is sold as Cialis for erectile dysfunction and BPH, as Adcirca for pulmonary arterial hypertension, and as generic tablets.
Also known as: Cialis, Adcirca.
Cialis comes as 5 mg, 10 mg and 20 mg tablets. Adcirca comes as 20 mg tablets.
The FDA Cialis label approves tadalafil for erectile dysfunction (ED), for the symptoms of benign prostatic hyperplasia (BPH), or both. For ED taken as needed, the starting dose is 10 mg before sexual activity (range 5 to 20 mg, no more than once a day); taken once daily for ED, 2.5 mg, up to 5 mg; for BPH, 5 mg once daily. It can be taken with or without food. The Adcirca label approves tadalafil for pulmonary arterial hypertension at 40 mg (two 20 mg tablets) once daily.
Tadalafil must not be taken with nitrates; if a nitrate is needed, the label says at least 48 hours should pass after the last dose. With strong CYP3A4 inhibitors such as ketoconazole or ritonavir, as-needed use is capped at 10 mg every 72 hours. Drinking 5 or more units of alcohol, alpha-blockers and other blood pressure drugs can add to its blood-pressure-lowering effect.
The FDA Cialis label gives a mean terminal half-life of 17.5 hours in healthy people, with peak levels between 30 minutes and 6 hours after a dose (median 2 hours), and steady state within 5 days of daily dosing. The Adcirca label reports a longer half-life, about 35 hours, in people with pulmonary arterial hypertension, and a median time to peak of 4 hours at 40 mg.
Numbers shown are the values Dose Track uses, listed only where they agree with the source above. Half-life varies from person to person and with injection site.