Megalis 20 mg commonly contains tadalafil 20 mg, a PDE5 inhibitor used to treat erectile dysfunction (ED) in adult men. It helps increase blood flow to the penis during sexual stimulation, making it easier to achieve and maintain an erection. Tadalafil does not increase sexual desire and requires sexual stimulation to work. The 20 mg strength is generally used on demand, rather than as a daily dose. It may begin working within about 30–60 minutes, and its effects can last for up to approximately 36 hours, although individual responses vary.
