Tazzle 20 mg is a medication primarily used to treat erectile dysfunction (ED) in men. The active ingredient in Tazzle is Tadalafil, the same active ingredient found in Cialis. Tadalafil works by improving blood flow to the penis, which helps men achieve and maintain an erection during sexual activity. Tadalafil is a PDE5 inhibitor, meaning it works by blocking the enzyme phosphodiesterase type 5 (PDE5), which is found in the smooth muscle of the blood vessels in the penis.