From the Guidelines
To minimize diarrhea when taking magnesium supplements, it is recommended to start with a low dose, such as 100-200mg daily, and gradually increase as tolerated, while also considering the use of liquid or dissolvable magnesium products, which are usually better tolerated than pills, as suggested by a study published in the Mayo Clinic Proceedings in 2023 1. When taking magnesium supplements, it is essential to be aware of the potential for gastrointestinal side effects, including diarrhea.
- The most recent and highest quality study, published in 2023, suggests that liquid or dissolvable magnesium products may be better tolerated than pills 1.
- Additionally, starting with a low dose and gradually increasing as tolerated can help minimize gastrointestinal effects.
- Taking magnesium supplements with food may also help reduce the risk of diarrhea.
- It is crucial to stay well-hydrated while taking magnesium supplements to prevent dehydration, especially if diarrhea occurs.
- If diarrhea persists, reducing the dose temporarily until symptoms improve may be necessary.
- It is also important to note that different magnesium compounds have varying bioavailability and absorption rates in the intestines, which can affect the likelihood of gastrointestinal side effects.
- If digestive issues continue despite these adjustments, consulting with a healthcare provider to explore alternative options or rule out other causes is recommended.
From the Research
Magnesium-Induced Diarrhea
- Magnesium-induced diarrhea can be diagnosed by measuring fecal output of soluble magnesium and fecal magnesium concentration 2
- The upper limits of fecal output of soluble magnesium and fecal magnesium concentration in normal subjects are 14.6 mmol per day and 45.2 mmol per liter, respectively 2
- Excessive ingestion of magnesium can be an important cause of chronic diarrhea, and quantitative fecal analysis for soluble magnesium is an accurate method of diagnosing magnesium-induced diarrhea 2
Managing Diarrhea
- Loperamide is an effective therapy for a variety of diarrheal syndromes, including acute, nonspecific diarrhea, and can be used to treat diarrhea in patients with magnesium-induced diarrhea 3, 4
- Loperamide works by decreasing peristalsis and fluid secretion, resulting in longer gastrointestinal transit time and increased absorption of fluids and electrolytes from the gastrointestinal tract 4
- Common adverse reactions to loperamide include cramps and nausea 4
Dietary Fiber and Prebiotics
- Viscous soluble fibers seem to be the best option in treating diarrhea, whereas prebiotics are more important in preventing and avoiding recurrence 5
- The use of prebiotics has encompassed not only prevention but also the treatment of distinct types of diarrhea, at different treatment moments, and with regard to various different markers of outcome 5
- Fiber supplementation in addition to loperamide may be effective in treating faecal incontinence in adults, but individual tailoring of treatment seems important to achieve the best outcome 6