Felodipine and Theophylline Interaction

Drug interaction information between Felodipine and Theophylline.

Felodipine and Theophylline have a documented major interaction in FDA labeling.

FDA drug labeling documents a major-severity interaction between Felodipine and Theophylline. 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

Felodipine

Calcium Channel Blocker

Drug B

Theophylline

Methylxanthine Bronchodilator

How They Interact

This blood pressure drug does not change the amount of theophylline that stays in your blood or how the liver handles it.

FDA Label Information

albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without sulbactam methylprednisolone atenolol metronidazole azithromycin metoprolol caffeine, dietary ingestion nadolol cefaclor nifedipine co-trimoxazole (trimethoprim and sulfamethoxazole) nizatidine diltiazem norfloxacin dirithromycin ofloxacin enflurane omeprazole famotidine prednisone, prednisolone felodipine ranitidine finasteride rifabutin hydrocortisone roxithromycin isoflurane Sorbitol (purgative doses do not inhibit theophylline absorption) isoniazid sucralfate isradipine terbutaline,...

Frequently Asked Questions

What SPL severity band is on file for Felodipine + Theophylline?

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

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

Theophylline has 86 labeled pairs on file vs Felodipine's 18. In the major band specifically: Felodipine has 2 (also Itraconazole); Theophylline has 27 (also Metoprolol, Albuterol, Omeprazole, Amoxicillin).

What mechanism field is on file for Felodipine and Theophylline?

This blood pressure drug does not change the amount of theophylline that stays in your blood or how the liver handles it.

Theophylline carries more major-labeled pairs than Felodipine

SPL source-record counts only. This page's band is major · classes on file: Felodipine (Calcium Channel Blocker); Theophylline (Methylxanthine Bronchodilator).

Theophylline has 27 major-labeled pairs vs Felodipine's 2.

Felodipine

2 major · 1 moderate · 15 minor · 18 total

Theophylline

27 major · 5 moderate · 54 minor · 86 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.