Sildenafil

• It is sold under the brand name Viagra.

Structure

• Sildenafil Chemical Structure –

Mode of action

• Sildenafil works by inhibiting the enzyme phosphodiesterase 5 (PDE5), which increases the breakdown of cGMP, an enzyme that controls blood flow in the penis. So, it increases blood flow in penis which results in erection of penis

• To work, sexual pleasure is necessary.

• Additionally, it causes the blood vessels in the lungs to enlarge.

Uses

• It is used to treat erectile dysfunction.