Ranitidine and Theophylline Interaction
Drug interaction information between Ranitidine and Theophylline.
Ranitidine and Theophylline have a documented major interaction in FDA labeling.
FDA drug labeling documents a major-severity interaction between Ranitidine 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.
How They Interact
Ranitidine can slow down how quickly your liver processes theophylline, which may cause the drug to build up to unsafe levels in your body.
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,...
Ranitidine Also Interacts With
- Risperidone major
- Valproate major
- Midazolam moderate
- Clonazepam minor
- Darunavir minor
Theophylline Also Interacts With
- Metoprolol major
- Albuterol major
- Omeprazole major
- Amoxicillin major
- Famotidine major
Frequently Asked Questions
What SPL severity band is on file for Ranitidine + 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 Ranitidine's 15. In the major band specifically: Ranitidine has 3 (also Risperidone, Valproate); Theophylline has 27 (also Metoprolol, Albuterol, Omeprazole, Amoxicillin).
What mechanism field is on file for Ranitidine and Theophylline?
Ranitidine can slow down how quickly your liver processes theophylline, which may cause the drug to build up to unsafe levels in your body.
Theophylline carries more major-labeled pairs than Ranitidine
SPL source-record counts only. This page's band is major · classes on file: Ranitidine (H2 Receptor Antagonist); Theophylline (Methylxanthine Bronchodilator).
Theophylline has 27 major-labeled pairs vs Ranitidine's 3.
3 major · 1 moderate · 11 minor · 15 total
- Other major peers for Ranitidine
- Risperidone
- Valproate
27 major · 5 moderate · 54 minor · 86 total
- Other major peers for Theophylline
- Metoprolol
- Albuterol
- Omeprazole
- Amoxicillin
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.
Read our methodology - how this data is sourced, computed, and verified.