Tadalafil, the active ingredient in Tadagra 20 mg, is a PDE5 inhibitor. It works by blocking the action of the enzyme phosphodiesterase type 5 (PDE5), which can constrict blood vessels and limit blood flow. By inhibiting this enzyme, Tadalafil helps the smooth muscle in the penis to relax, allowing for increased blood flow when sexually stimulated, thus enabling an erection.
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