Information about Sildenafil

Sildenafil Uses

Sildenafil is used in the treatment of erectile dysfunction.

How Sildenafil works

Sildenafil is a phosphodiesterase-5 (PDE-5) inhibitor. It works by relaxing the blood vessels in your penis, thereby increasing blood flow into the penis on sexual stimulation. This helps you achieve and maintain a hard, erect penis suitable for sexual activity.

Common side effects of Sildenafil

Flushing (sense of warmth in the face, ears, neck and trunk), Headache, Stiffness, Nosebleeds, Blurred vision, Indigestion, Muscle pain
Written By
Reviewed By
MD (Pharmacology), MBBS
Last updated:
18 Feb 2020 | 11:51 AM (UTC)
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Available Medicine for Sildenafil

PenegraZydus Cadila
139 to ₹3004 variant(s)
ViagraPfizer Ltd
525 to ₹10552 variant(s)
CavertaSun Pharmaceutical Industries Ltd
140 to ₹3373 variant(s)
AssuransCipla Ltd
200 to ₹18003 variant(s)
AlivherAkumentis Healthcare Ltd
1961 variant(s)
Penegra XpressZydus Cadila
160 to ₹1762 variant(s)
SilnafilEmcure Pharmaceuticals Ltd
2381 variant(s)
InstariseMacleods Pharmaceuticals Pvt Ltd
120 to ₹2322 variant(s)
JuanCadila Pharmaceuticals Ltd
72 to ₹2433 variant(s)
PAHMSN Laboratories
2131 variant(s)

Expert advice for Sildenafil

  • You have been prescribed Sildenafil for the treatment of erectile dysfunction.
  • It is best to take it an hour before sexual intercourse. But, you can take it anytime between 30 minutes and 4 hours before sexual activity.
  • Do not take it more than once a day.
  • Seek medical attention if the erection persists for more than 4 hours after sexual intercourse.
  • Do not use Sildenafil if you have recently taken nitrates (medicines used in angina or chest pain).
  • Do not take it if you have had a heart attack in the past 3 months, or stroke or heart failure in the past 6 months.

Frequently asked questions for Sildenafil


Q. Why is the use of Sildenafil contraindicated with nitrates?

Use of Sildenafil is harmful for patients taking nitrates or blood pressure-lowering medicines as their combined use can cause a severe fall in blood pressure, which can also result in death. However, if these medicines are to be taken together then it is advised to keep a time gap of 24 hours between the intake of Penegra and blood pressure-lowering medicines.

Q. Why does Sildenafil cause a fall in blood pressure (hypotension)?

Sildenafil has the property of relaxing the smooth muscle of the blood vessels and widening them which can cause a fall in blood pressure (hypotension). So, when used with blood pressure lowering medicines or nitrates, it can cause a severe fall in blood pressure, which could be fatal. Sildenafil should not be taken if you are taking nitrates for chest pain or you have a history of heart attack or stroke in the past 6 months.

Q. Can I get Sildenafil without a prescription?

No, you need a doctor's prescription to get Sildenafil since it is a prescription medicine. Your doctor will prescribe it only if they judge that it would be beneficial for you.

Q. Can I take Sildenafil for premature ejaculation?

No, Sildenafil is not known to have any beneficial effects in treating premature ejaculation. It is used for the treatment of erectile dysfunction.

Q. Can I take Sildenafil for the rest of my life?

Sildenafil is a prescription medicine and should only be taken for the duration that is advised by your doctor.

Q. Can I take Sildenafil in my twenties?

Yes, if prescribed by your doctor then Sildenafil can be taken in your twenties.

Q. Does Sildenafil affect fertility?

No, Sildenafil does not affect fertility, neither negatively nor positively.

Q. Does Sildenafil affect sperm?

Sildenafil does not affect sperm count or its health. It is a medicine that is used to treat erectile dysfunction.

Q. Does Sildenafil increase blood pressure?

No, Sildenafil is not associated with an increase in blood pressure. However, it can cause a decrease in blood pressure especially if taken with other blood pressure-lowering medications. Please consult your doctor before taking Sildenafil with any other medicine.

Q. Is Sildenafil safe to use in patients with diabetes?

Yes, if prescribed by your doctor then Sildenafil is safe to use in patients with diabetes.

Q. Can I take Sildenafil with paracetamol?

Yes, Sildenafil can be taken with paracetamol. No interactions between the 2 medicines or any harmful effects have been reported when they are used together.


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