If you mean “Which medications should not be taken with magnesium?”, the statement is a bit too broad. Magnesium supplements can interact with some medicines by reducing absorption or by affecting medication levels. People taking certain drugs should check with a pharmacist or clinician before using magnesium.
Common medication categories where caution is needed include:
- Certain antibiotics
- Tetracyclines (for example, doxycycline, tetracycline)
- Fluoroquinolones (for example, ciprofloxacin, levofloxacin)
Magnesium can bind these drugs in the gut and make them less effective.
- Thyroid hormone replacement
- Synthroid (levothyroxine) and similar medicines
Magnesium may reduce absorption.
- Synthroid (levothyroxine) and similar medicines
- Osteoporosis medicines
- Bisphosphonates such as alendronate
Magnesium can interfere with absorption.
- Bisphosphonates such as alendronate
- Some blood pressure or heart medicines
- Certain calcium channel blockers and other cardiovascular drugs may require timing adjustments or monitoring.
- Diuretics (“water pills”)
- Some increase magnesium loss; others may raise magnesium levels.
- Kidney disease medications or in people with reduced kidney function
- The body may not clear extra magnesium well, increasing the risk of high magnesium levels.
