Milk of Magnesia (MoM) is a common over-the-counter medication. Many wonder if this widely available remedy can offer relief for digestive discomfort, including diarrhea. Understanding MoM’s specific actions clarifies why it is not recommended for diarrhea.
How Milk of Magnesia Works
Milk of Magnesia contains magnesium hydroxide as its active ingredient. When ingested, magnesium hydroxide acts primarily as an osmotic laxative, drawing water from the body’s tissues into the intestines.
This increased water softens stool and increases the volume of intestinal contents, stimulating bowel contractions. These combined effects promote a bowel movement.
Why Milk of Magnesia Is Not for Diarrhea
Milk of Magnesia’s primary function is to draw water into the intestines and promote stool passage, making it counterproductive for managing diarrhea. Diarrhea is characterized by loose, watery stools and frequent bowel movements.
Using a laxative like Milk of Magnesia would intensify the condition, increasing fluid loss. This can exacerbate symptoms and lead to dehydration, a serious concern, especially in vulnerable populations.
When Milk of Magnesia Is Used
Milk of Magnesia is primarily used to treat occasional constipation. It softens hard stools and promotes regular bowel function, often providing relief within a few hours.
Beyond its laxative role, magnesium hydroxide also functions as an antacid. It neutralizes stomach acid, providing relief from indigestion, heartburn, and sour stomach. Smaller doses are used for these purposes compared to those for constipation.
Managing Diarrhea and When to Seek Medical Advice
Managing diarrhea focuses on preventing dehydration and allowing the digestive system to recover. Rehydration is achieved through oral rehydration solutions (ORS) that replenish lost fluids and electrolytes. Plain water, broths, or diluted juices can help.
Dietary adjustments are beneficial, such as consuming bland, easy-to-digest foods like bananas, rice, applesauce, and toast (BRAT diet). Over-the-counter medications like loperamide can slow bowel movements, while bismuth subsalicylate can reduce stool frequency and improve consistency.
These medications work differently from laxatives by affecting gut motility or by having antimicrobial and anti-inflammatory properties. Seek medical attention if diarrhea is severe, accompanied by signs of dehydration such as reduced urination or excessive thirst.
High fever, severe abdominal pain, or the presence of blood or black, tarry stools warrant immediate medical consultation. Diarrhea lasting more than two days in adults or 24 hours in infants and young children requires professional medical evaluation.