Doxycycline Hyclate and Bismuth Subsalicylate Interaction
Drug interaction information between Doxycycline Hyclate and Bismuth Subsalicylate.
Doxycycline Hyclate and Bismuth Subsalicylate have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Doxycycline Hyclate and Bismuth Subsalicylate. 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
Bismuth subsalicylate stops your body from absorbing doxycycline into your blood. This can prevent the antibiotic from working to kill bacteria.
FDA Label Information
Absorption of tetracyclines is impaired by bismuth subsalicylate.
Doxycycline Hyclate Also Interacts With
- Tetracycline moderate
- Doxycycline minor
- Carbamazepine minor
- Phenytoin minor
Bismuth Subsalicylate Also Interacts With
- Doxycycline minor
- Omadacycline minor
Frequently Asked Questions
What SPL severity band is on file for Doxycycline Hyclate + Bismuth Subsalicylate?
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?
Doxycycline Hyclate has 5 labeled pairs on file vs Bismuth Subsalicylate's 3. In the minor band specifically: Doxycycline Hyclate has 4 (also Doxycycline, Carbamazepine, Phenytoin); Bismuth Subsalicylate has 3 (also Doxycycline, Omadacycline).
What mechanism field is on file for Doxycycline Hyclate and Bismuth Subsalicylate?
Bismuth subsalicylate stops your body from absorbing doxycycline into your blood. This can prevent the antibiotic from working to kill bacteria.
Doxycycline Hyclate's labeled portfolio outnumbers Bismuth Subsalicylate
SPL source-record counts only. This page's band is minor · classes on file: Doxycycline Hyclate (Tetracycline Antibiotic (Antimalarial)); Bismuth Subsalicylate (Antidiarrheal / Antacid).
0 major · 1 moderate · 4 minor · 5 total
- Other minor peers for Doxycycline Hyclate
- Doxycycline
- Carbamazepine
- Phenytoin
0 major · 0 moderate · 3 minor · 3 total
- Other minor peers for Bismuth Subsalicylate
- Doxycycline
- Omadacycline
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.