Desloratadine and Erythromycin Interaction

Drug interaction information between Desloratadine and Erythromycin.

Desloratadine and Erythromycin have a documented minor interaction in FDA labeling.

FDA drug labeling documents a minor-severity interaction between Desloratadine and Erythromycin. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.

Drug A

Desloratadine

Second-Generation Antihistamine

Drug B

Erythromycin

Macrolide Antibiotic

How They Interact

Erythromycin interferes with the enzymes that process desloratadine, leading to higher-than-normal levels of the allergy drug in your body. These higher levels are generally considered safe and do not change how the drug works.

FDA Label Information

7 DRUG INTERACTIONS 7.1 Inhibitors of Cytochrome P450 3A4 In controlled clinical studies co-administration of desloratadine with ketoconazole, erythromycin, or azithromycin resulted in increased plasma concentrations of desloratadine and 3 hydroxydesloratadine, but there were no clinically relevant changes in the safety profile of desloratadine.

Frequently Asked Questions

What SPL severity band is on file for Desloratadine + Erythromycin?

Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.

Which drug in this pair has the larger labeled-interaction portfolio?

Erythromycin has 63 labeled pairs on file vs Desloratadine's 5. In the minor band specifically: Desloratadine has 5 (also Fluoxetine, Azithromycin, Ketoconazole, Cimetidine); Erythromycin has 53 (also Acetaminophen/Oxycodone, Alprazolam, Atorvastatin, Bromocriptine).

What mechanism field is on file for Desloratadine and Erythromycin?

Erythromycin interferes with the enzymes that process desloratadine, leading to higher-than-normal levels of the allergy drug in your body. These higher levels are generally considered safe and do not change how the drug works.

Erythromycin carries more major-labeled pairs than Desloratadine

SPL source-record counts only. This page's band is minor · classes on file: Desloratadine (Second-Generation Antihistamine); Erythromycin (Macrolide Antibiotic).

Erythromycin has 4 major-labeled pairs vs Desloratadine's 0. This page itself is in the minor band, not the major band.

Desloratadine

0 major · 0 moderate · 5 minor · 5 total

Erythromycin

4 major · 6 moderate · 53 minor · 63 total

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.