If you’re asking about the claim “Never use magnesium if you are taking any of the following medications”, the accurate version is more nuanced: magnesium supplements can interact with some medicines, mainly by reducing absorption or affecting how certain drugs work. It does not mean everyone taking these medications must avoid magnesium completely, but timing and medical advice may be important.
Common medication categories that can interact with magnesium include:
- Certain antibiotics
- Tetracyclines (e.g., doxycycline, tetracycline)
- Fluoroquinolones (e.g., 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 if taken too close together.
- Synthroid (levothyroxine) and similar medicines
- Bisphosphonates for osteoporosis
- Fosamax (alendronate) and related drugs
Magnesium can interfere with absorption.
- Fosamax (alendronate) and related drugs
- Some blood pressure or heart medications
- Certain calcium channel blockers and other medicines may require monitoring, especially in people with kidney problems.
- Diuretics (“water pills”)
- Some increase magnesium loss, while others can raise magnesium levels.
- Muscle relaxants or sedatives
- Magnesium may add to muscle-relaxing effects in some situations.
- Kidney disease medications or people with reduced kidney function
