Magnesium sulfate is a supplement that is most commonly indicated for treating magnesium deficiencies, relieving constipation or reliving muscle pain.
This salt, also referred to as Epsom salt, can be purchased pharmacies in the form of salts granules or powder to be added to soaking baths, or in the form of oral supplements, to be taken as a specified dose.
Although magnesium sulfate can be purchased without a prescription, you should only use it as directed by a doctor. Incorrect use can lead to complications. It is contraindicated for certain populations, like children, pregnant women, diabetics, and people with renal or cardiac disease.

What it's used for
Oral magnesium sulfate can be used for:
- Treating a magnesium deficiency;
- Treating constipation;
- Stimulating bowel movements prior to a surgical procedure, imaging exam or colonoscopy
In these cases, magnesium sulfate should be taken as prescribed, without exceeding the maximum daily dose. It should not be taken for longer than two weeks.
Magnesium sulfate salts have a naturally relaxing effect and can therefore be poured into baths or used for soaking compresses to relieve muscle pain, arthritis or fibromyalgia.
Can magnesium sulfate lead to weight loss?
Magnesium sulfate does not help you lose weight. The most common effect of oral magnesium sulfate is stimulating the intestines to promote the flow of stool through the intestines, which can be beneficial for treating constipation.
However, constipation is associated with symptoms like abdominal bloating, and taking magnesium sulfate can give you a false sense of weight loss.
Therefore, it is important to note that magnesium sulfate is not recommended for weight loss and should only be used as prescribed by a doctor.
How to take
The main ways to use magnesium sulfate are:
1. As a laxative
Magnesium sulfate taken orally to relieve constipation. Diluting the salt in 250 mL of filtered water and drink it on an empty stomach, preferably in the morning, before breakfast.
The normally recommended dose of magnesium sulfate for an intense and immediate laxative effect in adults is 5 g to 30 g of salt per day, which is equivalent to 1 teaspoon to 2 tablespoons.
2. To treat magnesium deficiency
To treat a magnesium deficiency, magnesium sulfate dosing should be guided by a doctor or registered dietitian on a case-by-base basis. Doses will depend on magnesium levels in the blood.
3. For baths
Pouring magnesium sulfate, or Epsom salts, into a warm bath can be beneficial for relieving muscle pain, arthritis or fibromyalgia.
It magnesium sulfate can also be used in foot baths or to make compresses.
Does magnesium sulfate detox the blood?
Magnesium sulfate does not detox the blood, and there is no scientific evidence that this salt can eliminate harmful substances from the body when used in baths or taken orally.
Possible side effects
The side effects of magnesium sulfate are minimum, but can lead to diarrhea, excess gas, stomach ache, and electrolyte imbalances. These are more likely to emerge if higher doses are used, or if it is used for more than 2 weeks.
High doses can lead to hypermagnesemia or magnesium overdose. These conditions cause symptoms like facial redness, excessive sweating, loss of reflexes, muscular weakness, shallow breathing, coma, respiratory arrest and cardiac arrest. These symptoms should be assessed immediately in an emergency room, as they can be life-threatening.
Also recommended: Hypermagnesemia: Symptoms, Normal Levels & Causes tuasaude.com/en/hypermagnesemiaContraindications for use
Magnesium sulfate is contraindicated in the following situations:
- Children under 2 years of age
- Pregnant or breastfeeding women
- Kidney or heart problems
- Chronic intestinal obstruction
- Crohn's disease, ulcerative colitis and other inflammations of the intestine
Magnesium sulfate should also not be used by people taking digoxin. It should not be used for more than 2 weeks.