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What is Which drug is not used for erectile dysfunction? and explain in detail?
Physiological erection occurs in response to the release of nitric oxide from noradrenergic - nor cholinergic nerves associated with parasympathetic discharge. Nitric oxide acts by activating guanylyl cyclase -| CGMP - cavernosal relaxation resulting in the erection. Thus the drugs which can be used for erectile dysfunction are: 1. PGE-l analogs eg Alprostadil 2. antagonists 3. Sildenafil (PDE - inhibitor) and its congeners tadalafil and vardenafil 4. Apomorphine (releases DA in CNS). Ref; KD Tripathi 8th ed.