Tadalis SX 20 is a medication used to treat erectile dysfunction (ED) in men. It contains the active ingredient Tadalafil, which belongs to a class of drugs called phosphodiesterase type 5 (PDE5) inhibitors. Tadalafil helps increase blood flow to the penis by relaxing the smooth muscles in the blood vessels, which in turn allows for an erection when a man is sexually stimulated. Tadalis SX typically takes effect within 30 minutes to 1 hour after taking the medication, and its effects can last for up to 36 hours. This long duration of action has earned it the nickname “the weekend pill.”