Tadact 20 mg is a medication primarily used to treat erectile dysfunction (ED) in men. It contains the active ingredient Tadalafil, which is a phosphodiesterase type 5 (PDE5) inhibitor. Tadalafil is the active component in Tadact 20 mg. It inhibits the enzyme PDE5, which is responsible for breaking down cyclic guanosine monophosphate (cGMP). By inhibiting PDE5, Tadalafil helps cGMP levels rise in penile tissues, leading to smooth muscle relaxation and increased blood flow, ultimately resulting in an erection.