Rifampin and Doxycycline Interaction
Drug interaction information between Rifampin and Doxycycline.
Rifampin and Doxycycline have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Rifampin and Doxycycline. 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
Rifampin speeds up how quickly your body breaks down doxycycline, which makes the antibiotic less effective at fighting infections.
FDA Label Information
Doxycycline Administered with rifampin (10 mg/kg daily) Decrease exposure Irinotecan Administered with an antibiotic regimen including rifampin (450 mg/day), isoniazid (300 mg/day), and streptomycin (0.5 g/day) IM Prevention or Management: Avoid the use of rifampin, a strong CYP3A4 inducer, if possible.
Rifampin Also Interacts With
- Darunavir major
- Bictegravir/Emtricitabine/Tenofovir major
- Glecaprevir/Pibrentasvir major
- Nirmatrelvir/Ritonavir major
- Pitavastatin major
Doxycycline Also Interacts With
- Tetracycline moderate
- Carbamazepine minor
- Bismuth Subsalicylate minor
- Phenytoin minor
- Doxycycline Hyclate minor
Frequently Asked Questions
What SPL severity band is on file for Rifampin + Doxycycline?
Compiled FDA labeling labels this pair moderate. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Rifampin has 137 labeled pairs on file vs Doxycycline's 9. In the moderate band specifically: Rifampin has 26 (also Probenecid, Theophylline, Apixaban, Aprepitant); Doxycycline has 2 (also Tetracycline).
What mechanism field is on file for Rifampin and Doxycycline?
Rifampin speeds up how quickly your body breaks down doxycycline, which makes the antibiotic less effective at fighting infections.
Rifampin carries more major-labeled pairs than Doxycycline
SPL source-record counts only. This page's band is moderate · classes on file: Rifampin (Rifamycin Antibiotic); Doxycycline (Tetracycline Antibiotic).
Rifampin has 8 major-labeled pairs vs Doxycycline's 0. This page itself is in the moderate band, not the major band.
8 major · 26 moderate · 103 minor · 137 total
- Other moderate peers for Rifampin
- Probenecid
- Theophylline
- Apixaban
- Aprepitant
0 major · 2 moderate · 7 minor · 9 total
- Other moderate peers for Doxycycline
- Tetracycline
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.