The Interaction Between Fruit Juice and Allegra

If you are 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, or 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.

Let's talk about why fruit juice can be a problem with Allegra, why this is, and what you can do to avoid the interaction if you enjoy fruit juice.

Glasses of orange juice, grapefruit juice and multivitamine juice, juice squeezer and fruits on wood
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What Is Allegra (Fexofenadine)?

Allegra (fexofenadine), is a non-sedating antihistamine that is available over-the-counter (OTC) without a prescription. Since becoming available over the counter, 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.

For this reason, it is important for people to know that taking Allegra along with various fruit juices, especially orange and grapefruit juice, reduces the absorption of Allegra by more than one-third, therefore making the medicine less effective.

Interaction of Allegra (Fexofenadine) and Fruit Juice

Allegra depends on specialized receptors on cells that line the small intestine called organic anion transporting polypeptides or OATPs. OATP proteins help chemicals (such as some medications) cross the biological membranes that are otherwise impermeable to these drugs.

Fruit juices, such as grapefruit juice, orange juice, and apple juice contain compounds that inhibit OATPs and therefore limit the absorption of Allegra in the body. (One of these compounds is thought to be naringin.) Unfortunately, it doesn't take a lot of fruit juice for this inhibition to occur.

Consumption of drinks with as little as 5 percent juice can result in inhibition of OATPs. Overall, taking Allegra with fruit juice may decrease the absorption by nearly 40 percent or more, making the medicine far less effective in the treatment of allergy symptoms

A decrease of 40 percent of the dose doesn't mean that you will get 40 percent of the effect of the drug. A certain amount of the drug is required for any effect to be noticed, and a 40 percent reduction in dose might mean that you will get absolutely no help from that dose.

The compounds in the juice which inhibit the absorption of Allegra are thought to be in higher concentrations in commercially available juices as well as those which are calcium-fortified. Since the compounds of fruit juice which inhibit the absorption of Allegra are present in whole fruit as well, whole oranges, grapefruit, or apples should likely also be avoided during the time during which Allegra is being absorbed as well.

Avoid fresh fruit or fruit juices for 1 to 2 hours before and after taking Allegra. Otherwise, the effectiveness of Allegra will be significantly reduced, and allergy symptoms or hives will likely be left uncontrolled.

Other Allergy Medications and Fruit Juice

If you're finding it tricky to take a twice a day medication and juggle your intake of fruit juice, there are other options. You may wish to switch to a different allergy medication which is not affected by the intake of fruit or fruit juice. There are a number of different medications available for allergic rhinitis, just as there are other medications for hives (urticaria.)

For those with moderate to severe hayfever, or for people with hives, a medication such as Zyrtec (cetirizine) or Xyzal (levocetirizine) may be slightly more effective than Allegra. These medications, however, can cause drowsiness in some people.

Claritin (loratadine) is another option which is similar in efficacy to Allegra.

Other Medications Which May Be Affected by Fruit Juice

It's not only Allegra levels in the body that may be affected by the intake of fruit or fruit juice. Fruits may also inhibit the gastrointestinal uptake of some antibiotics, some blood pressure medications, some cholesterol medications, and even some heart medications such as beta-blockers. 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.

Bottom Line on Fruit Juice and Allegra

Since the intake of fruit or fruit juice can interfere significantly with the absorption of Allegra, the timing of your medication should be scheduled at least two hours before or two hours after drinking fruit juice. If this presents a problem, there are other effective hay fever and hive medications which may be used instead.

Thankfully, the symptoms treated by Allegra such as hay fever and hives are not usually life-threatening, though they can significantly reduce your quality of life. There are reasons beyond symptoms, however, to pay attention to the interaction of fruit juice and Allegra. It's simply not a good idea financially to purchase and take the time to take a medication which will not be absorbed.

This interaction does serve as a good example of how medications may not just interfere with each other, but with the foods in our diet. With any medication, it's important to read the small print and to talk with your doctor and pharmacist about any potential interactions. Take some time to learn more about how to reduce your risk of adverse effects and drug interactions.

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