The Interaction Between Fruit Juice and Allegra

If you're taking prescription or over-the-counter Allegra for allergies, you should be aware that these medications can interact with fruit juices such as:

• Apple juice
• Grapefruit juice
• Orange juice

In fact, if you drink fruit juice or even fruit punch within an hour or two of taking your medicine, you may lose the effectiveness of the drug entirely.

What Is Allegra?

Allegra (fexofenadine), is a non-sedating antihistamine that's available over-the-counter (OTC).

Since becoming available without a prescription, as well as being approved for young children (as young as six months), Allegra will likely become even more popular for people with allergy symptoms.

However, taking Allegra along with juice reduces its absorption by between 30% and 60%, depending on the juice, making the medicine less effective.

Allegra and Fruit Juice

To be absorbed into your bloodstream, Allegra depends on specialized receptors on cells that line your small intestine called organic anion transporting polypeptides or OATPs.

OATP proteins help chemicals (including some medications) cross the biological membranes that are otherwise impermeable to these drugs.

Apple, grapefruit, and orange juices contain compounds (including one called naringin) that inhibit OATPs, thus limiting how much Allegra your body absorbs. It takes very little juice for this inhibition to occur.

A decrease of 60% of the dose doesn't mean that you'll get 40% of the drug's effect. It takes a certain amount of the drug for you to notice any effect, and a significant reduction in dose might mean you'll get absolutely no help from it.

Researchers believe the absorption-inhibiting compounds in the juice have higher concentrations in commercially available juices as well as those that are calcium-fortified.

Those compounds are present in whole fruit too.

It's safest to avoid fresh fruit or fruit juices for 1 to 2 hours before and after taking Allegra. Otherwise, they could significantly reduce the effectiveness of Allegra and leave your allergy symptoms or hives uncontrolled.

Allergy Drug Options

If you're finding it tricky to juggle a twice-a-day medication and fruit intake, you have other options.

You may want to switch to a different allergy medication that isn't affected by fruit. A number of different medications are available for allergic rhinitis and hives (urticaria.)

If you have hives or moderate-to-severe hayfever, a medication like Zyrtec (cetirizine) or Xyzal (levocetirizine) may be slightly more effective than Allegra, anyway. (However, they cause drowsiness in some people.)

Claritin (loratadine) is another option that's similar to Allegra.

Other Drugs Affected by Juice

It's not only Allegra levels in the body that may be affected by the intake of fruit or fruit juice.

Fruit may also interfere with enzymes in the small intestine that metabolize drugs, causing too much or too little of the drug to be absorbed the body. Some of these drugs include:

• Statin drugs that lower cholesterol, such as Zocor (simvastatin) and Lipitor (atorvastatin)
• Drugs that treat high blood pressure, such as Procardia, adalat CC and beta-blockers
• Anti-anxiety drugs such as buspirone
• Drugs that treat abnormal heart rhythms such as Pacerone and Nexterone (both amiodarone)
• Antibiotics such as ciprofloxacin or Cipro, levofloxacin, and itraconazole

Some researchers have even suggested that any medication should be taken outside of the four-hour window surrounding the consumption of fruit or fruit juice.

That way, you eliminate potential health risks and don't waste your money on drugs that are rendered ineffective by your diet.

A Word From Verywell

This interaction is a good example of how medications may not just interfere with each other, but with the foods in your diet. With any medication, it's important to read the small print and to talk with your healthcare provider and pharmacist about any potential interactions. Also be sure to ask your practitioner, pharmacist, or other healthcare provider if you can drink grapefruit juice while taking your medications, which also has potential for drug interaction.