Udenafil, the active component of Zudena Pills , is a member of the drug class known as phosphodiesterase Type 5 (PDE 5) inhibitors.
It works by raising Cyclic Guanosine Monophosphate (cGMP) levels and suppressing the PDE-5 enzyme.
The blood vessels in the penile region enlarge due to elevated cGMP levels, increasing the blood flow required for a firm erection.
However, this medicine will only work in the presence of sexual stimulation.