Viagra (brand name for Sildenafil) is primarily used for the treatment of erectile dysfunction (ED) in men. Erectile dysfunction is the inability to achieve or maintain an erection sufficient for sexual intercourse. Viagra works by increasing blood flow to the penis, which helps to achieve and sustain an erection when a man is sexually aroused.
Primary Uses of Viagra:
- Erectile Dysfunction (ED):
- Viagra is most commonly prescribed for men with ED, a condition where a man has trouble getting or keeping an erection firm enough for sexual activity.
- It works by inhibiting the enzyme phosphodiesterase type 5 (PDE5), which helps relax the blood vessels in the penis and allows for increased blood flow during sexual stimulation.
- Pulmonary Arterial Hypertension (PAH):
- Sildenafil is also used under the brand name Revatio to treat pulmonary arterial hypertension (PAH), a condition that causes high blood pressure in the arteries of the lungs. It helps relax and widen the blood vessels in the lungs, which reduces the heart’s workload and improves exercise capacity in people with PAH.
Off-Label Uses (Less Common):
- Sexual Arousal Disorders in Women: Some research and off-label use have explored Sildenafil’s effects on women with sexual arousal disorders, although its efficacy for this purpose is still debated.
- Raynaud’s Disease: Sildenafil has also been used off-label to treat Raynaud’s phenomenon, a condition where blood flow to fingers and toes is reduced, leading to pain and discoloration.
How Viagra Works:
Viagra is a PDE5 inhibitor, which means it blocks the enzyme that typically breaks down cyclic GMP (cGMP), a molecule that helps relax blood vessels. By inhibiting PDE5, Viagra allows cGMP levels to rise, resulting in improved blood flow, especially to the penis when a man is sexually aroused.
Important Considerations:
- Viagra typically takes effect within 30 to 60 minutes after ingestion and can last for up to 4-5 hours. It should not be taken more than once per day.
- It is important to note that sexual arousal is necessary for Viagra to work; it does not cause an erection without sexual stimulation.
Common Side Effects:
- Headache
- Flushing
- Indigestion
- Nasal congestion
- Dizziness
- Visual disturbances (e.g., blue-tinted vision)
Note: Viagra should be used under the supervision of a healthcare provider, especially if the individual has pre-existing heart conditions or is taking other medications that may interact with sildenafil.