Megalis 20 mg works by inhibiting the enzyme PDE5, which is responsible for breaking down cGMP (cyclic guanosine monophosphate). This chemical plays a key role in relaxing the smooth muscles of the blood vessels in the penis, which results in increased blood flow. By blocking PDE5, Tadalafil helps to maintain higher levels of cGMP, allowing men to achieve and sustain an erection when sexually stimulated.
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