Magnesium Sulfate Side Effects

Medically reviewed by Drugs.com. Last updated on Sep 11, 2023.

Applies to magnesium sulfate: crystal, foam, powder, powder for solution, powder for suspension, spray.

Precautions

If your symptoms do not improve within a few days or if they become worse, check with your doctor.

Laxative use: Before using this medicine, talk to your doctor first

• If you are pregnant or breastfeeding.
• If you noticed a sudden change in bowel habits that continued for more than 2 weeks.
• If you have stomach pain, nausea, or vomiting.
• If you are on a magnesium-restricted diet.
• If you have already used a laxative for longer than a week.

Laxative use: Stop using this medicine and check with your doctor if you have rectal bleeding or do not have a bowel movement after use.

Soaking solution use: Do not use this medicine if you are pregnant or have diabetes, unless your doctor tells you otherwise.

Soaking solution use: Stop using this medicine and check with your doctor if you have a skin irritation or infection.

Serious side effects of magnesium sulfate

Along with its needed effects, magnesium sulfate may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking magnesium sulfate:

Other side effects of magnesium sulfate

Some side effects of magnesium sulfate may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For healthcare professionals

Applies to magnesium sulfate: injectable solution, intravenous solution, oral and topical powder for reconstitution.

Metabolic adverse events

• Frequency not reported: Hypermagnesemia (signs include drowsiness, loss of reflexes, nausea, vomiting, flushing, thirst, hypotension, hypothermia, bradycardia, confusion, electrolyte and fluid abnormalities, slurred speech, muscle weakness, muscle paralysis, blurred or double vision, CNS depression, respiratory depression, respiratory paralysis, circulatory collapse, renal failure, coma, cardiac arrhythmias, cardiac arrest), hypocalcemia with tetany secondary to hypermagnesemia, alkalosis^[Ref]

Gastrointestinal

• Frequency not reported: Colic, gastrointestinal irritation, watery diarrhea, paralytic ileus^[Ref]

Hypersensitivity

• Frequency not reported: Hypersensitivity reactions^[Ref]

Local

• Frequency not reported: Irritation and pain at the injection site^[Ref]

See also:

Frequently asked questions

• When is the best time to take magnesium, morning or night?
• Should I take magnesium with or without food?
• Does magnesium help with restless leg syndrome (RLS)?
• Does magnesium help with headaches and migraines?
• Does magnesium help with weight loss?

Further information

Magnesium sulfate side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer