High doses of magnesium glycinate may cause diarrhea, gas, or stomach pain. Very high or long-term use can lead to magnesium toxicity. People with kidney or heart disease, or certain neuromuscular ...

Too much magnesium may cause diarrhea and abdominal cramps. In severe cases, it can lead to difficulty breathing, irregular heartbeat, and death. Severe magnesium toxicity is not all that common.

Lindsay Cook, PharmD, is a consultant pharmacist working with long-term care facilities. High doses of magnesium glycinate may cause diarrhea, gas, or stomach pain. Very high or long-term use can lead ...