From the Guidelines
Magnesium glycinate is generally well-tolerated, with the most significant side effects being nausea, anorexia, and mild ataxia at doses exceeding 400 mg, as well as increased urinary excretion at high doses. The side effects of magnesium glycinate include:
- Digestive issues: Nausea, anorexia
- Neurological issues: Mild ataxia
- Other effects: Increased urinary excretion at high doses, rare cases of anaphylaxis with high IV doses These side effects are typically mild and often resolve on their own as your body adjusts to the supplement. To minimize side effects, start with a lower dose (around 200-300 mg daily) and gradually increase as tolerated, as recommended by recent guidelines 1. It's also important to note that people with kidney problems should be cautious and consult a doctor before taking magnesium supplements, as they may be at risk for magnesium toxicity. Additionally, while magnesium glycinate is less likely to cause digestive side effects compared to other forms of magnesium, high doses may still cause gastrointestinal tract intolerance, as seen in some studies 1. However, the most recent and highest quality study 1 suggests that the primary concern with high doses of magnesium glycinate is increased urinary excretion and rare cases of anaphylaxis with high IV doses.
From the Research
Side Effects of Magnesium (Mg) Glycinate
- The side effects of magnesium glycinate include bloating, vomiting, constipation, and nausea, as it relaxes intestinal smooth muscles, similar to its effect on skeletal muscles 2.
- High doses of magnesium or prolonged use may allow sufficient absorption into the systemic circulation to cause renal or other organ toxicity 3.
- Minor side effects reported in children treated with magnesium for asthma include epigastric or facial warmth, flushing, pain and numbness at the infusion site, dry mouth, malaise, and hypotension 4.
- Oral magnesium supplementation in chronic kidney disease stages 3 and 4 was found to be safe and well tolerated, with no serious adverse events related to the study medication reported 5.
Mechanisms of Action
- Magnesium decreases motility of the intestine through the beta adrenergic receptor pathway, which can lead to discomforting symptoms such as bloating, vomiting, constipation, and nausea 2.
- The laxative effect of magnesium is thought to be due to a local effect in the intestinal tract, where poorly absorbable magnesium ions exert an osmotic effect and cause water to be retained in the intestinal lumen 3.
Interactions with Other Substances
- Magnesium and drugs use the same transport and metabolism pathways in the body, which means that there is always a potential risk of interaction with the magnesium status when taking one or more drugs 6.
- Magnesium can interfere with the gastrointestinal absorption of certain drugs, such as tetracycline antibiotics, and simultaneously, the physiological function of minerals such as magnesium may be impaired by a drug 6.