How Long Does an Erection Last on ED Medication?

The short answer

ED medication does not give you one continuous erection that lasts for hours. Instead, it opens a window during which you can get and keep an erection when you are sexually aroused. Between moments of stimulation, the erection naturally softens — which is completely normal and healthy.

The length of that window depends mainly on which active ingredient you take.

Typical windows by ingredient

• Sildenafil (the active ingredient in Viagra and Kamagra): usually starts working in around 30–60 minutes and offers a helpful window of a few hours.
• Tadalafil: works far longer, with an effective window that can stretch across a much larger part of a day or into the next — which is why it is sometimes called the "weekend" option. See the Tadalafil guide.
• Vardenafil: broadly similar in timing to sildenafil.
• Avanafil: tends to act quickly, with a shorter overall window.

These are general patterns, not promises. Read the patient information leaflet for the specific medicine you have.

Why an individual erection isn't "timed"

PDE5 inhibitors work by relaxing blood-vessel walls in the penis so blood can flow in once arousal triggers the process. They do not create arousal by themselves. So during the active window:

• An erection appears in response to stimulation.
• It softens again when stimulation stops.
• It can return as long as the medicine is still active and you are aroused.

Think of it as making the natural mechanism easier to switch on, not as a timer counting down a single erection. For more on the underlying biology, see how PDE5 inhibitors work and erectile dysfunction explained.

What affects how long it lasts for you

Several everyday factors change both onset and duration:

• Food: a heavy or fatty meal can slow down and weaken the effect of sildenafil in particular.
• Alcohol: more than a small amount can reduce the response and make erections harder to achieve.
• Individual biology: metabolism, age, and overall vascular health all play a part.
• Arousal and setting: relaxed, genuinely aroused conditions help the medicine do its job.

When an erection lasts too long

A prolonged, often painful erection that lasts more than 4 hours is called priapism, and it is a medical emergency. Untreated, it can cause lasting damage. Seek urgent medical care straight away — do not wait to see if it resolves on its own.

This is rare, but knowing the warning sign matters more than knowing the average duration.

Setting realistic expectations

The goal of ED medication is not a marathon erection. A realistic, healthy outcome is:

• Being able to get an erection firm enough for sex when aroused.
• Keeping it long enough to be satisfying.
• Having a comfortable margin of time so you don't feel rushed.

If you find your erections fade too quickly even within the active window, or the medicine doesn't seem to help, that is worth discussing with a doctor or pharmacist — it can sometimes point to dosing, timing, technique, or an underlying health issue. Importantly, ED itself can be an early sign of cardiovascular disease, so persistent problems deserve a proper check-up.

Important safety note

Never combine any PDE5 inhibitor with nitrate medicines (often prescribed for chest pain) or recreational "poppers" (amyl nitrites). The combination can cause a dangerous drop in blood pressure.

Browse the erectile-dysfunction range or shop all to compare options, and always read the leaflet before you start.

General information only — not medical advice. Always read the patient information leaflet and consult a doctor or pharmacist before starting any medication.