Tadalafil 20 mg is the maximum as-needed dose for ED. Learn about its uses, how long it lasts, side effects, and how to save on your prescription. Medscape - Erectile dysfunction, pulmonary arterial hypertension-specific dosing for Adcirca, Cialis (tadalafil), frequency-based adverse effects, comprehensive interactions, contraindications. For most individuals, the recommended starting dose of tadalafil is 10 mg per day taken before sexual activity (tadalafil for use as needed). Depending on the adequacy of the response or side effects, the dose may be increased to 20 mg or decreased to 5 mg a day. Tadalafil is used to treat men who have erectile dysfunction (also called sexual impotence). Tadalafil belongs to a group of medicines called phosphodiesterase 5 (PDE5) inhibitors. Tadalafil is in a class of medications called phosphodiesterase (PDE) inhibitors. It works to treat erectile dysfunction by increasing blood flow to the penis during sexual stimulation. Find patient medical information for Tadalafil (Cialis, Adcirca, and others) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Easy-to-read patient tips for tadalafil covering how it works, benefits, risks, and best practices. Tadalafil is a generic drug prescribed for erectile dysfunction and other conditions. Learn about the drug’s dosages, form, strengths, and more. Tadalafil increases blood flow to particular areas of the body and is used to treat erectile dysfunction. Learn about side effects, interactions and indications. Tadalafil is prescribed for benign prostatic hyperplasia, erectile dysfunction, and pulmonary arterial hypertension. Learn about side effects and more.