Magnesium citrate is an absorbable form of magnesium used to manage occasional constipation because of its ability to improve bowel movements.
While generally safe when used within the recommended limit of 350 mg, higher doses of magnesium citrate can cause gastrointestinal side effects.
Magnesium citrate increases water retention in the stool, leading to an increase in the frequency of bowel movements and a softer stool, making it easier to pass. While this property is beneficial for people who want to treat constipation, it may not be suitable for others, as doses above 350 mg daily can increase the frequency of loose, watery stools.
Extremely high doses of magnesium citrate can lead to more serious side effects, such as rectal bleeding (blood in the stool). Stop taking the medication immediately and consult your healthcare provider if you observe this side effect.
Magnesium citrate can also cause abdominal cramps or stomach pain, especially when taken in larger doses. Consult your healthcare provider if the abdominal cramps last for more than two weeks.
Magnesium citrate can trigger nausea and vomiting, especially when taken on an empty stomach or at a higher dose.
Magnesium citrate can also make you feel dehydrated if you have diarrhea or experience vomiting without taking fluids to replenish the water loss.
Do not take magnesium citrate without first talking to your healthcare provider if you:
Magnesium citrate can also interact with certain medications, including:
- Bisphosphonates (such as alendronate)
- Diuretics (such as furosemide)
- Certain antibiotics
- Proton pump inhibitors (such as omeprazole).
Consult your doctor before taking magnesium citrate if you are currently taking any other medications.
Additionally, magnesium citrate supplements during pregnancy may delay the onset of breast milk flow. It’s best to check in with your healthcare provider before using magnesium citrate if you are pregnant.
Some ways you can manage magnesium citrate effects include:
- Take magnesium within recommended doses (about 350 mg daily)
- Consider taking magnesium citrate in smaller doses if you want to reduce its laxative effect
- Drink plenty of water to prevent dehydration.
- Consider taking magnesium citrate with food to reduce diarrhea and stomach pain.
- If you are taking other medications, take them at least 2 hours before or after taking magnesium citrate.
- Talk to your doctor if you have stomach pain, vomiting or nausea lasting more than 2 weeks.
- Consider taking magnesium at night or when you are closer to a restroom.

