Cialis and Grapefruit: Is There an Interaction?

Cialis® is one of the most well-known medications for treating erectile dysfunction approved by the U.S. Food and Drug Administration (FDA), but if you want to take it safely, you’d better watch your consumption of one food: grapefruit.

Unlike orange juice, grapefruit juice can impact how Cialis is metabolized in your body, leading to increased levels of the medication in your system. That can be dangerous for a variety of reasons.

Does this mean you have to stop drinking grapefruit juice every morning? It’s a little complicated. Read on to learn why there’s caution, and what to do with your breakfast beverage for your safety.

You should avoid mixing grapefruit and Cialis because grapefruit has the ability to increase the concentration levels of Cialis in your bloodstream, which may cause an increased risk of side effects.

Let’s back up for a second, though. 

Like Viagra® and Stendra®, Cialis (tadalafil) works to increase blood flow to the penis, which can treat erectile dysfunction and help to improve your sexual satisfaction — it’s also used in the treatment of benign prostatic hyperplasia, otherwise known as prostate enlargement.

In its role as a PDE5 inhibitor, tadalafil acts as a vasodilator to promote the flow of blood to the penis.

Grapefruit can increase the amount of Cialis in your bloodstream.

CYP3A4 (an enzyme in your intestine) is responsible for the metabolism of many drugs, including Cialis. Grapefruit can inhibit CYP3A4. Therefore, grapefruit can block the metabolism of Cialis, and more of the drug enters the body’s circulation.

Grapefruit has been known to cause similar effects when taken with some antihypertensives, as well as other PDE5 inhibitors like sildenafil (generic Viagra) and vardenafil. 

It has even been known to cause strokes when taken with certain migraine medications.

For the best results, avoid drinking or eating grapefruit around the time you intend to use Cialis.

While grapefruit consumption may seem harmless, you may actually experience heightened side effects of Cialis. 

Tadalafil and grapefruit may not produce noticeable side effects in smaller amounts, but there’s no clear way to predict how many side effects you’ll experience from a tadalafil grapefruit combination — or how severe they’ll be.

Keep your eyes open for: 

• Headaches

• Indigestion

• Back pain

• Muscle pain

• Nasal congestion

• Flushing

If you feel signs of less common but serious side effects like changes in vision, changes in hearing, priapism (an erection lasting more than four hours) or chest pain — whether you’ve consumed grapefruit juice or not with Cialis — seek medical advice immediately.

Here’s an important spoiler: grapefruit is not the secret answer to the question, “What can I take to enhance Cialis?” Trying to create some Cialis grapefruit mixture in the name of harder erections is unsafe, and rolling the dice on those side effects risks is how some men end up in the emergency room.

In the case of grapefruit and Cialis, this liquid or the fruit itself produces an unwanted effect — known as a “drug interaction.” 

Cialis also interacts with drugs like alpha blockers and nitrates.

There are plenty of ways to give Cialis the best conditions to do its job, and those might be better considered enhancements. Things on that list include timing your dose properly and talking to your healthcare provider about the most appropriate dose for you.

“How long does grapefruit stay in your system” is a different question. According to the journal, American Family Physician, an 8oz glass of grapefruit juice can stay in your digestive system for up to 72 hours.

That being the case, anyone taking Cialis should not eat grapefruit or drink grapefruit juice for three days before starting the medication.

If you are taking a daily dose of Cialis (a.k.a. tadalafil 2.5mg or 5mg taken every day), you may not be able to consume grapefruit at all. Be sure to talk to your healthcare provider about this possible tadalafil interaction.

Cialis is high up on the recommendation list when it comes to managing erectile dysfunction.

However, care must be taken to avoid the effects of grapefruit juice when taking Cialis (namely, the increased risk of experiencing side effects).

Learn more about the effects Cialis can have on your body by speaking with a qualified healthcare provider.