Magnesium supplements can interact with several common medications. In some cases, the combination reduces how well the medicine works; in others, it may increase the risk of side effects or dangerously alter magnesium levels.
You should be especially careful with magnesium if you take:
- Antibiotics
- Especially tetracyclines and fluoroquinolones such as Doxycycline, Ciprofloxacin, and Levofloxacin
- Magnesium can block absorption and make the antibiotic less effective. (Office of Dietary Supplements)
- Osteoporosis medications (bisphosphonates)
- Such as Alendronate
- Magnesium can reduce absorption of these drugs. (Office of Dietary Supplements)
- Diuretics (“water pills”)
- Examples include Furosemide, Hydrochlorothiazide, and Spironolactone
- These medicines can either lower or raise magnesium levels in the body. (Office of Dietary Supplements)
- Proton pump inhibitors (PPIs)
- Such as Omeprazole, Esomeprazole, and Lansoprazole
- Long-term use may cause low magnesium levels. (Office of Dietary Supplements)
- Heart and blood pressure medications
- Magnesium may enhance the effects of some calcium channel blockers and other heart medicines, potentially causing low blood pressure or irregular heartbeat. (EatingWell)
- ADHD stimulant medications
- Magnesium may affect absorption of amphetamine-based medications in some cases. (EatingWell)
- Kidney disease medications or conditions
- People with kidney problems can accumulate too much magnesium, leading to toxicity. (Mayo Clinic)
Important: magnesium from food is usually safe. Most interactions involve magnesium supplements, laxatives, or antacids containing magnesium.
If you tell me which medication you’re taking, I can check whether magnesium is safe with it.

