rewrite this title 15 Medications That Should Never Be Mixed With Grapefruit

Grapefruit (Citrus paradisi) is a common citrus fruit often consumed as grapefruit juice. It is high in vitamin C, potassium, fiber, and other important nutrients. Grapefruit can interact with numerous medications taken by mouth, affecting how well the medicines may work.

About 50% of all drugs are metabolized (broken down and processed) by an enzyme in the gastrointestinal (GI) tract called CYP3A4. Grapefruit and grapefruit juice can prevent the enzyme from working.

Medications that may be affected by grapefruit include statins, amiodarone, estrogen, and clopidogrel. It is important to discuss potential medication interactions with a healthcare provider to determine if grapefruit is safe for you to consume.

HMG-CoA reductase inhibitors, also known as statins, are popular medications for treating high cholesterol. Examples include Zocor (simvastatin), Lipitor (atorvastatin), and Crestor (rosuvastatin). Statins known to interact with grapefruit juice include simvastatin, atorvastatin, and lovastatin.

Statins are metabolized through CYP3A4 enzymes. Taking a statin with grapefruit will lead to higher levels of the drug staying in your body. This can increase your risk for side effects caused by statins, including liver damage, muscle pain and breakdown (rhabdomyolysis), and kidney failure.

Benzodiazepines are depressants used to treat numerous conditions, including anxiety, muscle spasms, and seizures. Benzodiazepines affected by grapefruit include Valium (diazepam), Versed (midazolam), and Klonopin (clonazepam). Grapefruit does not appear to affect Xanax (alprazolam).

Benzodiazepines are metabolized through CYP3A4 enzymes. Studies show that grapefruit juice decreases how much benzodiazepine is removed from the body and increases how much remains in the blood, increasing your risk of side effects. Benzodiazepine side effects include loss of consciousness, drowsiness, confusion, diarrhea, headache, and tremors.

Calcium channel blockers (CCBs) are medications used to treat high blood pressure and other heart conditions. Examples of CCBs include Procardia (nifedipine), Norvasc (amlodipine), and Cardizem (diltiazem).

Calcium channel blockers are metabolized through CYP3A4 enzymes. Taking grapefruit may increase levels of CCBs in your blood, increasing your risk for side effects, including headache, lightheadedness, low blood pressure (hypotension), and slow heart rate (bradycardia).

Some researchers believe that grapefruit may also affect drug levels by reducing how quickly the stomach empties.

Sandimmune or Neoral (cyclosporine) are common immunosuppressants used to prevent transplanted organs from being rejected by the body. Cyclosporine is metabolized through CYP3A4 enzymes.

Grapefruit affects cyclosporine by increasing how much of the drug your body absorbs and increasing cyclosporine levels in the blood. This may also increase the risk of side effects caused by cyclosporine, including diarrhea, increased hair growth, muscle or joint pain, unusual bruising or bleeding, and seizures.

BuSpar (buspirone) is a medication used to treat anxiety.

Buspirone is metabolized through CYP3A4 enzymes. Grapefruit increases how much buspirone your body absorbs and its levels in your blood. This increases your risk for buspirone side effects, such as drowsiness, dizziness, headache, confusion, and agitation.

Entocort EC and Uceris (budesonide) are corticosteroids used to treat inflammatory conditions like Crohn’s disease and ulcerative colitis.

Budesonide is metabolized by CYP3A4. Eating or drinking grapefruit may increase levels of budesonide in the blood, which in turn may increase the risk of side effects. Side effects of budesonide include stomach pain, vomiting, fatigue, muscle pain, and mood changes.

Estrogen is a hormone used to replace estrogen levels and treat various conditions associated with low estrogen levels, like hot flashes. Medications that contain estrogen include birth control pills, conjugated estrogens like Premarin, and estradiol like Estrace. Estrogen is also metabolized by CYP3A4 enzymes.

Grapefruit appears to slow how quickly your body breaks estrogen down and increase how much estrogen you absorb. This may increase estrogen levels in your body, increasing your risk of side effects like vomiting, weight gain or loss, nervousness, hair growth or loss, weakness, and joint pain.

Pacerone or Cordarone (amiodarone) are prescription medications for treating abnormal heart rhythms (arrhythmias). Amiodarone is metabolized by many enzymes, including CYP3A4.

Grapefruit can increase the effects of amiodarone by increasing how much of the drug is absorbed in your body. This can lead to worsening arrhythmias and side effects, such as headache, loss of appetite, restlessness, nervousness, and excessive sweating.

Studies have estimated that grapefruit juice can increase amiodarone levels in the blood by over 50%.

Allegra (fexofenadine) is an antihistamine used to treat allergies. Fexofenadine is available as a prescription or OTC.

Grapefruit affects the drug transporter’s organic anion transporting polypeptide (OATP), which can lead to less fexofenadine entering the blood.

Studies have found that grapefruit juice lowers fexofenadine levels. Higher concentrations of grapefruit lead to increasingly lower fexofenadine levels. The manufacturer of fexofenadine also found that those taking the drug with grapefruit juice saw more skin swelling and itching, suggesting that the interaction lowers the drug’s effectiveness.

Fexofenadine’s effect on the OATP transporter may only last for a short time, so separating a fexofenadine dose from grapefruit juice by at least 4 hours will likely prevent any drug interaction.

Tegretol (carbamazepine) is a medication commonly used to treat seizures. Carbamazepine is primarily metabolized by CYP3A4 enzymes.

Grapefruit increases the levels of carbamazepine in your blood, thereby increasing the drug’s effect. This raises the risk of side effects caused by carbamazepine, like drowsiness, difficulty speaking, dry mouth, confusion, or headache. You may also experience more seizures.

Seroquel (quetiapine) is a medication prescribed to treat conditions like bipolar disorder, schizophrenia, and depression. Quetiapine is metabolized through CYP3A4 enzymes.

Grapefruit decreases how fast the body gets rid of quetiapine, potentially affecting how well the medicine works and increasing your risk for side effects. Side effects associated with quetiapine include dizziness, generalized pain, weakness, unusual dreams, and seizures.

Prograf (tacrolimus) is an immunosuppressant that helps prevent the body from rejecting transplanted organs. It is primarily metabolized through the CYP3A4 enzyme.

Grapefruit can lower how quickly the body metabolizes tacrolimus and increase blood levels of the drug, which increases your risk for side effects. Tacrolimus side effects include headache, diarrhea, weakness, and seizures. One study found that 200 milliliters of grapefruit juice daily with 3 milligrams a day of tacrolimus increases the drug’s levels in the blood threefold.

Effient (prasugrel) is a blood thinner that helps prevent blood clots in certain people at risk. Prasugrel is metabolized in the body by the CYP3A4 enzyme.

In a study evaluating how grapefruit juice affects prasugrel, researchers found that the fruit lowered the amount of prasugrel activated in the body. Despite this, grapefruit seems to have little to no effect on how well the medicine prevents blood clots.

Plavix (clopidogrel) is an antiplatelet that helps prevent blood clots, especially in people at risk for a heart attack or stroke. Clopidogrel is primarily metabolized by the CYP2C19 enzyme.

Grapefruit may lower the amount of clopidogrel activated in the body and blood levels of clopidogrel, reducing the medication’s effectiveness. One study found that grapefruit juice lowered blood levels of clopidogrel by more than 80% and impacted its antiplatelet effects, which could lead to a higher risk of blood clots.

Viagra (sildenafil) is a phosphodiesterase-5 inhibitor used to treat erectile dysfunction and pulmonary arterial hypertension. Sildenafil is metabolized by the CYP3A4 enzyme.

Grapefruit can decrease how quickly your body metabolizes sildenafil, increasing the potential for side effects, which include headache, hypotension (low blood pressure), heartburn, vision loss, and ringing in the ears. Absorption of sildenafil can increase by over 23% when taken with grapefruit.

When you take a medication by mouth, the body can break down (metabolize) and absorb the drug in numerous ways. Grapefruit affects this breakdown process, causing too much or too little drug to be available in the body.

About 50% of all drugs are metabolized by an enzyme found in the gastrointestinal (GI) tract called CYP3A4. Grapefruit and grapefruit juice can block the enzyme from working, causing a medication to stay in your body longer than it should. Blocking CYP3A4 also makes it easier for medication to move into your bloodstream, which increases your risk for serious side effects.

A chemical called furanocoumarin might be responsible for the CYP3A4 interaction. Furanocoumarin is found in many citrus products, including grapefruit, Seville oranges, limes, and pomegranate. The chemical is also metabolized by CYP3A4, blocking other products (including medication) from connecting to the enzyme and being metabolized.

Grapefruit also affects proteins that move a drug into your cells to be absorbed (also called drug transporters). This leads to less of the drug entering the blood and the drug not working as well. One grapefruit or 200 milliliters (about 1 cup) of grapefruit juice is believed to be enough to affect drug metabolism.

The severity of a grapefruit and drug interaction depends on various factors, including the person, the drug, the amount of CYP3A4 and other metabolizing enzymes you have in your body, and the amount of grapefruit consumed.

Although the interaction between grapefruit and medications does not typically cause issues, changes in drug levels can cause unwanted side effects or affect treatment. To prevent these interactions, it is best to avoid consuming grapefruit with any medication known to interact with it.

For certain medications (like fexofenadine), you can separate the time you take the drug from the time you consume grapefruit. However, this is not an option for all medications.

If you consume grapefruit and begin experiencing any abnormal symptoms or side effects, talk with your healthcare provider. Symptoms may be related to the medication (whether too much or too little is in the body) or the health condition the medication is supposed to be treating.

If you are interested in consuming grapefruit while taking medication, talk with your healthcare provider. They can help you determine if grapefruit interacts with any medications you are taking or are interested in taking.

Grapefruit is known to interact with certain medications taken by mouth, affecting how well the medicines may work.

Examples of medications that grapefruit may affect include statins, amiodarone, estrogen, and clopidogrel. Talk with your healthcare provider to determine if any medications you are taking or are interested in taking may interact with grapefruit.