Tazzle is a brand name for a medication that contains the active ingredient tadalafil. Tadalafil is a phosphodiesterase type 5 (PDE5) inhibitor, and it is primarily used to treat erectile dysfunction (ED) in men. Tazzle contains tadalafil as its active ingredient. Tadalafil works by increasing blood flow to the penis when a man is sexually aroused, facilitating the achievement and maintenance of an erection. Tazzle is prescribed to men who have difficulty achieving or sustaining an erection sufficient for sexual activity due to ED.