Common side effects of sildenafil can occur in more than 1 in 100 people, but taking too much can cause unpleasant side effects as well. Some more serious reactions should be reported to a healthcare professional immediately.

Sildenafil is considered to be a relatively safe drug, which is why it is available without a prescription.

However, it’s not a good idea to take too much.

Dr Douglas Savage, a general practitioner specializing in sexual medicine and senior medical consultant at the Center for Men’s Health, spoke to Patient Info about what could happen if you exceed the recommended dose.

“I would definitely not recommend it,” he said. He added that you wouldn’t end up with a permanent erection, “more likely a really bad headache.”

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Erectile dysfunction medications should never be taken with recreational drugs, the site adds.

In addition to headaches, the NHS says taking too much sildenafil can cause dizziness, indigestion, a stuffy nose and impaired vision.

“Talk to your doctor if you’ve taken too much sildenafil and are worried about these side effects,” Healthy Body recommends.

There are also potentially more serious side effects associated with taking the drug.


Serious side effects are rare and occur in less than 1 in 1,000 people, according to the NHS.

Stop taking sildenafil and call a doctor immediately if you experience chest pain, prolonged and sometimes painful erections for more than four hours, or sudden decrease or loss of vision.

Very serious side effects also include a severe skin reaction, the symptoms of which “may include fever, severe peeling and swelling of the skin, blisters in the mouth, genitals and around the eyes.” the NHS states.

The drug can also cause seizures, and immediate medical help should be sought for this.

According to the National Institutes of Health (NIH), the drug, available in tablet or liquid form, should be taken between four hours and 30 minutes before sexual activity.

Sildenafil should generally not be taken more than once every 24 hours, advises the NIH.

To get the most out of sildenafil, do not drink a lot before taking it.

“A beer or a few glasses of wine is not likely to stop or delay the work of sildenafil. But drinking a lot of alcohol can make it harder to get an erection, ”says the NHS.

Do not drink grapefruit juice if you are taking sildenafil for pulmonary hypertension, as it interferes with the way the medicine works.

You can eat and drink normally while taking sildenafil to get an erection.

Erectile dysfunction can often be improved for some people if you make lifestyle changes, such as quitting smoking and not taking recreational drugs.

Still, most men sometimes fail to get or maintain an erection, according to the NHS.