From the Guidelines
Combining lactose with Miralax (polyethylene glycol 3350) is generally safe for most people, as there are no significant drug interactions between the two substances. Miralax works by drawing water into the intestines to soften stool and increase bowel movements, while lactose is a sugar found in dairy products that some people have difficulty digesting 1. If you are lactose intolerant, consuming lactose might cause digestive symptoms like bloating, gas, or diarrhea, which could potentially compound the laxative effects of Miralax. However, there is no dangerous chemical interaction between the two.
When taking Miralax, the standard dose is 17 grams (about 1 heaping tablespoon) dissolved in 4-8 ounces of water, juice, or other liquid once daily, as recommended by the American Gastroenterological Association 1. It typically works within 1-3 days. If you're considering taking both substances together because you're experiencing constipation, it's worth noting that lactose intolerance itself can sometimes cause diarrhea, so adding Miralax might not be necessary.
Some key points to consider:
- Miralax is an osmotic laxative that can help increase bowel movements and soften stool 1.
- Lactose is a sugar found in dairy products that can cause digestive symptoms in people with lactose intolerance.
- There are no significant drug interactions between lactose and Miralax, but lactose intolerance can cause similar symptoms to Miralax, such as bloating, gas, or diarrhea 1.
- It's best to consult with your healthcare provider about your specific situation, especially if you have ongoing digestive issues or other health concerns.
In terms of managing constipation, the American Gastroenterological Association recommends the use of fiber supplementation, osmotic laxatives like Miralax, and stimulant laxatives as needed 1. Lactulose, a synthetic disaccharide, can also be considered for the treatment of constipation, especially if symptoms have failed to improve with fiber and OTC laxatives 1. However, the use of lactulose may be limited by its side effects, such as bloating and flatulence.
From the Research
Combining Lactose with Miralax (Polyethylene Glycol 3350)
There are no direct studies on the combination of lactose with Miralax (polyethylene glycol 3350). However, we can look at the individual components:
- Lactose is a disaccharide made up of glucose and galactose, and its digestion by lactase and subsequent absorption occurs in the small intestine 2, 3, 4.
- Polyethylene glycol 3350 (Miralax) is a laxative used to treat constipation, and its safety and efficacy have been evaluated in several studies 5, 6.
Safety of Polyethylene Glycol 3350
The safety of polyethylene glycol 3350 has been evaluated in patients with functional constipation and occasional constipation:
- A randomized, placebo-controlled trial found that polyethylene glycol 3350 was safe and well tolerated in patients with functional constipation, with no significant difference in adverse events between the treatment and placebo groups 5.
- A double-blind trial found that polyethylene glycol 3350 was effective and safe in subjects with self-reported occasional constipation, with no deaths, serious adverse events, or discontinuations due to adverse events reported 6.
Lactose Intolerance
Lactose intolerance occurs when lactase activity is reduced in the brush border of the small bowel mucosa, leading to symptoms such as abdominal pain, bloating, flatulence, and diarrhea:
- The nutritional management of lactose intolerance should always preserve breastfeeding, and lactose reduction or elimination should be transient, with eliminated food replaced with other similar in calorie, protein, mineral, and vitamin content 2.
- Lactose intolerance has a high prevalence worldwide, and its diagnosis is essential to undertake an adequate treatment, with different methods available, including genetic test, hydrogen breath test, quick lactase test, and lactose tolerance test 4.
Potential Interactions
While there are no direct studies on the combination of lactose with Miralax, it is possible that individuals with lactose intolerance may experience worsening symptoms if they consume lactose while taking Miralax:
- The fermentation of lactose by gut microbiota can lead to symptoms of lactose intolerance, and the use of Miralax may alter the gut microbiota, potentially exacerbating these symptoms 3, 4.
- However, the safety and efficacy of polyethylene glycol 3350 have been established in patients with constipation, and its use is not contraindicated in individuals with lactose intolerance 5, 6.