Understanding Tadalafil: Phosphodiesterase Type 5 (PDE5) Inhibition:   Tadalafil belongs to the class of medications known as PDE5 inhibitors. Its primary role is to inhibit the action of PDE5, an enzyme responsible for breaking down cyclic guanosine monophosphate (cGMP). cGMP and Smooth Muscle Relaxation:   In the absence of PDE5 inhibition, cGMP levels rise in the penile...