Take at a Different Time of Day
Numerous minerals, including aluminum (found in many antacids), bismuth (in Pepto-Bismol),
, interfere with the absorption of medications in the tetracycline family (and vice versa).
The reason is the minerals and the drugs attach to each other and form insoluble chemicals that simply pass out of the digestive tract. The best solution is to avoid taking supplements that contain these minerals within the 2 hours before or after your dose of tetracycline medication.