Tadalafil is an FDA-approved prescription medication used to treat erectile dysfunction (ED), benign prostatic hyperplasia (BPH), and improve exercise ability in patients with pulmonary arterial hypertension (PAH). It comes in various strengths and forms, including tablets and oral jelly, and its effects may last up to 36 hours. Tadalafil is contraindicated in patients with hypersensitivity to its components or those using organic nitrates, and it may cause side effects like headache and dyspepsia.