Skip to main content

Drug Interactions between clarithromycin and fexofenadine

This report displays the potential drug interactions for the following 2 drugs:

Edit list (add/remove drugs)

Interactions between your drugs

Minor

clarithromycin fexofenadine

Applies to: clarithromycin and fexofenadine

Coadministration with erythromycin has been shown to increase the oral bioavailability of fexofenadine. The proposed mechanism is erythromycin inhibition of the intestinal efflux of fexofenadine via P-glycoprotein transporter. In addition, erythromycin may decrease biliary excretion of fexofenadine. In 24 healthy volunteers, coadministration of fexofenadine 120 mg twice a day and erythromycin 500 mg every 8 hours resulted in a 82% and 109% increase in the steady-state fexofenadine peak plasma concentration (Cmax) and systemic exposure (AUC), respectively, compared to administration of fexofenadine alone. However, no increase in adverse effects or QTc interval were noted. No studies have been performed using clarithromycin or troleandomycin, but similar results are possible given their similarities to erythromycin. Fexofenadine had no effect on the pharmacokinetics of erythromycin.

References

  1. (2001) "Product Information. Allegra (fexofenadine)." Hoechst Marion Roussel
  2. (2001) "Product Information. Allegra-D (fexofenadine-pseudoephedrine)." Chattem Consumer Products

Switch to consumer interaction data

Drug and food interactions

Moderate

fexofenadine food

Applies to: fexofenadine

GENERALLY AVOID: Coadministration with large amounts of certain fruit juices, including grapefruit, orange and apple, may decrease the oral bioavailability of fexofenadine. The proposed mechanism is inhibition of drug efflux via intestinal organic anion transporting polypeptides (e.g., P-glycoprotein), of which fexofenadine is a substrate. In a five-way crossover study with 10 healthy volunteers, 1/4-strength grapefruit juice, grapefruit juice, orange juice and apple juice (300 mL with drug administration and 150 mL every 1/2 hour for up to 3 hours, total volume 1.2 L) reduced the mean area under the plasma concentration-time curve (AUC) of a 120 mg dose of fexofenadine by 23%, 67%, 72% and 77%, respectively, compared to water. Mean peak plasma concentration (Cmax) was similarly affected. The clinical significance of these changes is unknown. However, results from studies using histamine-induced skin wheals and flares found that the size of wheal and flare was significantly larger when fexofenadine was administered with either grapefruit or orange juices compared to water.

MANAGEMENT: To maximize plasma levels and therapeutic effects, fexofenadine should be taken with water. In addition, patients should refrain from consuming large amounts of grapefruit, orange, or apple juice.

References

  1. Bailey DG, Dresser GK, Munoz C, Freemar DJ, Kim RB (2001) "Reduction of fexofenadine bioavailability by fruit juices." Clin Pharmacol Ther, 69, PI-82
  2. Dresser GK, Bailey DG, Leake BF, et al. (2002) "Fruit juices inhibit organic anion transporting polypeptide-mediated drug uptake to decrease the oral availability of fexofenadine." Clin Pharmacol Ther, 71, p. 11-20

Switch to consumer interaction data

Minor

clarithromycin food

Applies to: clarithromycin

Grapefruit juice may delay the gastrointestinal absorption of clarithromycin but does not appear to affect the overall extent of absorption or inhibit the metabolism of clarithromycin. The mechanism of interaction is unknown but may be related to competition for intestinal CYP450 3A4 and/or absorptive sites. In an open-label, randomized, crossover study consisting of 12 healthy subjects, coadministration with grapefruit juice increased the time to reach peak plasma concentration (Tmax) of both clarithromycin and 14-hydroxyclarithromycin (the active metabolite) by 80% and 104%, respectively, compared to water. Other pharmacokinetic parameters were not significantly altered. This interaction is unlikely to be of clinical significance.

References

  1. Cheng KL, Nafziger AN, Peloquin CA, Amsden GW (1998) "Effect of grapefruit juice on clarithromycin pharmacokinetics." Antimicrob Agents Chemother, 42, p. 927-9

Switch to consumer interaction data

Therapeutic duplication warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.

See also

Report options

Loading...
QR code containing a link to this page

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer