Can I take milk of magnesia while breastfeeding? - Evidence Based Babies
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Is it safe to breastfeed while taking milk of magnesia?

Can I take milk of magnesia while breastfeeding?

If you’re a breastfeeding mother who’s also struggling with constipation, you’ve probably thought about or heard about using milk of magnesia. Some people may even recommend it to help with weight loss. The use of laxatives to help with weight loss is not recommended.

What is milk of magnesia?

Magnesium hydroxide, known under the more common trade names or brand names such as Phillips’ Milk of Magnesia, Dulcolax Milk of Magnesia, Pedia-Lax Chewable Tablet, Ex-Lax Milk of Magnesia and just plain old milk of magnesia, is a type of oral saline/osmotic laxative. It works by drawing water to the bowel from surrounding tissue. The water then helps to soften and moisten the stool. It also helps to increase bowel motions and bowel movement.

Saline laxatives are known to be fast and effective, which makes it an excellent choice for short term use for occasional constipation, such as the constipation new mothers may experience after giving birth or during the early postpartum period due to stronger pain medication.

Lactulose laxatives also known as stimulant laxatives on the other hand are slow acting compared to saline laxatives. It is thought to be the better option for chronic constipation.

Is it safe to take milk of magnesia while breastfeeding?

According to Hales medication, magnesium and phosphate salts will be rapidly eliminated by the kidneys in normal individuals, and only around 15%-30% of magnesium salts may be absorbed from the gastrointestinal tract.

Although there isn’t much research available on the use of high dosages of magnesium salts or of the phosphates, the breast cell controls the electrolyte concentrations of milk closely and laxatives are unlikely to alter breastmilk.

Milk of magnesia is unlikely to enter the breast milk, and when it does, it will be very small amounts and there’s been no evidence of milk of magnesia reducing the milk supply or affecting milk production or breastfed babies in any way.

The potential side effects of milk of magnesia

The most commonly experienced side effect of taking milk of magnesia is diarrhea. If you experience nausea or diarrhea while taking milk of magnesia, it would be best to stop taking it as soon as possible.

More serious side effects include rectal bleeding which can indicate a serious health complication. If you experience rectal bleeding while taking milk of magnesia, it would be best to stop taking it immediately and contact your health care provider for medical attention immediately.

Another side effect includes the overuse of milk of magnesia which may result in the dependence of laxatives to help with bowel movements. This is why it’s only recommended for short term use when natural remedies are not helping with constipation.

Alternatives to milk of magnesia

There are many natural remedies that can help with constipation, both short term and chronic constipation before trying medicines.

– Stay well hydrated

As mentioned above, things like laxatives or even fiber, draw water into the bowel to help soften and moisten the bowel movements. So, drinking plenty of water should make it easier to keep things going.

– Consume enough fiber

Dietary fiber foods help to increase the weight and size of your stool and help to soften it. A bulky stool is easier to pass, which helps to make you more regular and decreases the risk of constipation. Dietary fiber is found in food such as whole grains and fruits and vegetables.

– Regular exercise

Some basic lifestyle changes may be all it takes. Exercise increases the breathing and heart rate which helps to stimulate muscles and nerves in the mucosal lining of the intestines. This activates squeezing of the intestinal muscles which helps move foods through the large intestine faster.

This entire process helps to reduce the amount of water that your body absorbs from the food, which helps keep the stool soft and moist, which is easier to pass than dry and hard stool.

– Drink caffeinated coffee

Caffeinated coffee has long been well known to help people get their bowel movements going. Coffee contains acids that are shown to boost the levels of the hormone gastrin which stimulate colon contractions.

Caffeine has long been the center of breastfeeding safe foods talk. There is still much misinformation regarding the use of caffeine while breastfeeding.

Caffeine has been shown to enter breastmilk in small quantities, but it’s rare for it to bother a baby unless high amounts are consumed very often. It is recommended to not consume more than 200mg of caffeine while breastfeeding, although many mothers do consume more without it affecting their babies. Some babies may be more sensitive to caffeine than others. It is important to note that caffeine also has a very long half-life in babies. So, if your baby is one of those who are affected by caffeine, it’s best to limit or even avoid the use of caffeine.

– Eat probiotic foods

Chronic constipation can sometimes be due to having an imbalance of bacteria in the gut and consuming more probiotic foods can help improve the bacteria balance and in turn reduce, or even prevent constipation.

Important notes regarding the use of milk of magnesia while breastfeeding

The good news is that the use of milk of magnesia is believed to be perfectly safe while breastfeeding. No side effects in breastfed infants or the milk supply have been reported.

It’s always a good idea to first try and figure out what the cause of constipation may be for you and whether a few lifestyle changes will work for you instead of immediately starting the use of stool softeners. Especially if you may have a medical condition that may be causing your symptoms of constipation which may require specific prescription medication.

Milk of magnesia have previously been banned in the United Kingdom (UK) for containing too much sulphate for safe human consumption. Too much sulphate can affect a person’s health.

Natural remedies should be the first go to for the relief and prevention of short term and chronic constipation. Only after natural remedies have failed to work, should medicinal intervention be considered.

Remember to always check the safety of medication for breastfeeding mothers before taking it, especially if it’s over the counter medications.

If at any time you need any help regarding anything related to breastfeeding, do not hesitate to get into contact with an International Board Certified Lactation Consultant (IBCLC).

If you’re ever worried about you or your baby’s health in any way, or you’d just like some medical advice, you should contact your health care provider immediately.

Additional information and resources:

Hales medication

Magnesium Hydroxide

National library of medicine: drug information

The breastfeeding network: Indigestion and Breastfeeding

Infant risk centre: Over-The-Counter Treatments for GI Complaints

The breastfeeding network: Constipation Treatment in Breastfeeding Mothers



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