29–32: A Few Erectile Dysfunction and Prostate Medications

A few erectile dysfunction and prostate medications deserve attention regarding grapefruit interactions:

  1. Sildenafil (Viagra)
  2. Tadalafil (Cialis)
  3. Tamsulosin (Flomax)
  4. Silodosin (Rapaflo)

Erectile dysfunction medications like sildenafil and tadalafil work by relaxing blood vessels, which increases blood flow to an erection.


Because other blood vessels relax with these medications as well, increased blood levels of these drugs caused by grapefruit can decrease blood pressure (8).

Moreover, prostate enlargement medications such as tamsulosin can also cause increased dizziness and low blood pressure when taken with grapefruit (19).

Alternatives: Another class of prostate enlargement medications, which includes finasteride and dutasteride, is not significantly affected by grapefruit (19).

SUMMARY:Grapefruit should not be consumed with erectile dysfunction medications or certain prostate enlargement medications.

Should You Give Up Grapefruit?

While this article lists 32 common medications that interact with grapefruit, it is not a complete list.

Drugs.com offers a drug interaction checker that you can use to check your medications for interactions.Additionally, Rxlist.com lists some less common medications that also interact with grapefruit.

It’s important to remember that just one whole grapefruit or about one large glass of juice is enough to change the blood levels of many drugs. And some of these medications may have serious side effects when they interact with grapefruit.

If you are currently taking medications with grapefruit interactions, switch to an alternative drug or stop consuming grapefruit.

If in doubt, reach out to your doctor or pharmacist for personalized advice.

SUMMARY:Even small amounts of grapefruit can interact with some medications and cause serious side effects.

The Bottom Line

Grapefruit interferes with proteins in the small intestine and liver that normally break down many medications.

Eating grapefruit or drinking grapefruit juice while taking these medications can lead to higher levels in your blood — and more side effects.

With some drugs, with even small amounts of grapefruit can cause severe side effects. Therefore, the combination should be avoided.

These drugs may be marked with a grapefruit interaction warning by your pharmacy.

Make sure your doctor and pharmacist know if you regularly consume grapefruit. They can help you decide whether it’s safe to consume while on certain medications.