Safety · Supplement
Magnesium: side effects, safety & interactions
Very safe with normal kidneys; excess is excreted, with loose stools the main sign of too much. In kidney impairment it
- Overall grade
- Grade B
- Last revised
- 0
- graded outcomes
- 0
- references listed
Assembled by the app from other entries in this library. It adds no evidence of its own — follow the links to the entries it draws on.
The evidence in words
Safety profile
Very safe with normal kidneys; excess is excreted, with loose stools the main sign of too much. In kidney impairment it can accumulate dangerously. It binds several drugs in the gut (see timing interactions).
Interactions to respect
Levothyroxine — Binds thyroid hormone in the gut — separate by 4 hours. · Antibiotics — Chelates quinolones/tetracyclines — separate by 2+ hours. · PPIs — Prolonged PPI use can drive magnesium clinically low. · Blood-pressure medications — Mild additive blood-pressure lowering.
What Magnesium is
Magnesium is an essential mineral concentrated in bone and inside cells, where it is a cofactor for over 300 enzymes including every reaction that uses ATP. Intakes below the requirement are common on Western diets. Forms differ mainly in absorption and bowel tolerance: glycinate and citrate absorb well, oxide is mostly a laxative, and L-threonate is marketed for the brain.
The honest bottom line
One of the better-value supplements: 200–400 mg glycinate or citrate in the evening. Expect modest help with sleep, blood pressure, and migraine — most in those who were low to begin with.
Related reading
Entries that share this one's tags or conditions.
- Magnesium for Blood pressureEvidence grade B — ~2–3 mmHg in meta-analysisEvidence grade B
- Magnesium for MigraineEvidence grade B — Prophylactic; 400–600 mgEvidence grade B
- MagnesiumA cofactor in 300+ reactions that a large fraction of adults under-consume — real, modest benefits for sleep, blood pressure, and migraine.Evidence grade B
- Magnesium for Correcting low statusEvidence grade A — Common dietary shortfallEvidence grade A
Sources
This entry lists no references of its own — it is assembled from the entries it links to, whose sources are on their pages.
Last revised . A grade is this entry's reading of the evidence, not medical advice.