Drug Interaction Report

Doxycycline and magaldrate should not be taken orally at the same time. Products that contain magnesium, aluminum, calcium, iron, and/or other minerals may interfere with the absorption of doxycycline into the bloodstream and reduce its effectiveness. If possible, it may be best to avoid taking magaldrate while your are being treated with doxycycline. Otherwise, you should separate dosing by 2 to 4 hours, doxycycline should be taken at least 2 hours before and not less than 6 hours after Suprep Bowel Prep (magnesium/potassium/sodium sulfates), or doxycycline and magaldrate should be taken as directed by your healthcare provider. Talk to your healthcare provider if you are unsure whether your medications contain something that could potentially interact or if you have questions on how to take this or other medications you are prescribed. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Consumer information for this interaction is not currently available.

GENERALLY AVOID: The oral bioavailability of quinolone and tetracycline antibiotics may be reduced by concurrent administration of preparations containing polyvalent cations such as aluminum, calcium, iron, magnesium, and zinc. Therapeutic failure may result. The proposed mechanism is chelation of quinolone and tetracycline antibiotics by di- and trivalent cations, forming an insoluble complex that is poorly absorbed from the gastrointestinal tract. Reduced gastrointestinal absorption of the cations should also be considered.

MANAGEMENT: Concomitant administration of oral quinolone and tetracycline antibiotics with preparations containing aluminum, calcium, iron, magnesium, and/or zinc salts should generally be avoided. Otherwise, the times of administration should be staggered by as much as possible to minimize the potential for interaction. Quinolones should typically be dosed either 2 to 4 hours before or 4 to 6 hours after polyvalent cation preparations, depending on the quinolone and formulation. Likewise, tetracyclines and polyvalent cation preparations should typically be administered 2 to 4 hours apart. The prescribing information for the antibiotic should be consulted for more specific dosing recommendations.

Information for this minor interaction is available on the professional version.