That headline is too dramatic. Magnesium supplements aren’t universally forbidden with particular medicines, but magnesium can interact with several medications—most often by reducing how much of the medicine your body absorbs.
Medicines that deserve particular attention
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Levothyroxine: Magnesium can reduce its absorption. It should generally be taken separately from magnesium supplements.
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Tetracycline antibiotics: Examples include doxycycline and tetracycline. Magnesium can bind to these medicines and reduce absorption.
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Fluoroquinolone antibiotics: Examples include ciprofloxacin and levofloxacin. Magnesium can interfere with absorption, so timing is important.
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Bisphosphonates: Medicines such as alendronate can have reduced absorption when taken with magnesium.
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Some medicines that affect kidney function or magnesium levels: The interaction can go in either direction, depending on the drug.
Another important issue: kidney disease
People with significantly reduced kidney function can accumulate magnesium because the kidneys normally remove excess magnesium. High-dose magnesium supplements can therefore be dangerous.
Don’t stop a prescribed medicine just because you saw this headline. In many cases, the solution is simply to separate the medications by several hours rather than avoid magnesium entirely.
If you give me the name and dose of your medication, I can tell you whether it interacts with magnesium and what spacing is generally recommended.
