What’s the Problem?
When used “off-label” in children, the laxative powder MiraLax has been linked to severe neuropsychiatric problems including tremors, tics, obsessive-compulsive behaviors, and more.
What is MiraLax?
MiraLax (generic: polyethylene glycol 3350 or “PEG 3350”) is an over-the-counter treatment for occasional constipation. The drug works by bringing water into the bowels, which helps keep the digestive system regular. MiraLax is manufactured by Bayer, and was approved by the U.S. Food & Drug Administration (FDA) in February 1999.
FDA Questions Laxative Use as Childhood Remedy
At the request of the FDA, scientists at Children’s Hospital of Philadelphia (CHOP) are studying how children metabolize PEG 3350 and whether its use could be tied to psychiatric problems in children, according to the New York Times. The laxative is given routinely (and sometimes daily) to constipated children, yet it has never been approved for long-term daily use, neither in adults nor children. FDA has received reports of obsessive-compulsive behavior, tics, tremors and other neuropsychiatric side effects in children taking PEG 3350 laxatives.
MiraLax Contains Antifreeze Ingredients
In 2008, FDA tested 8 batches of Miralax and found small amounts of the car antifreeze ingredients ethylene glycol (EG) and diethylene glycol (DEG) in all batches. These were impurities from the manufacturing process, according to the agency. The tests were performed because many of the adverse events reported were consistent with ethylene glycol poisoning.
MiraLax Side Effects
- Kidney Damage
- Acute Kidney Injury
- Kidney Failure (End-Stage Renal Disease or “ESRD”)
- Oxalate Nephropathy
- Acidic blood
- Obsessive-Compulsive Behavior
- Neuropsychiatric Events
- Mood Swings
- And more
Empire State Consumer Project
In 2012, the Rochester, New York-based Empire State Consumer Project (ESCP) filed a petition with the FDA to reopen its investigation into the safety of PEG 3350. The petition was granted in 2014, with the goal of the research being to determine whether PEG 3350 breaks down into the toxic chemicals ethylene glycol and diethylene glycol in the body, increasing the risk for adverse psychiatric events in children.
- Study published in the journal Alimentary Pharmacology and Therapeutics (AP&T) in June 2008 found that orally administered PEG-3350 is minimally absorbed, rapidly excreted and primarily eliminated via feces.
- Study published in Clinics in Colon and Rectal Surgery in February 2009 found that mechanical bowel preparation products (MBP) like MiraLax offer no benefit as a preoperative measure and question their place in current surgical practices.
- Study published in PLOS ONE in February 2012 found that standard bowel cleansing preparations alter the mucosal-adherent microbiota. The findings underscore the importance of considering the confounding effects of bowel preparation when designing experiments exploring the gut microbiota, according to the researchers.
- 2014 Study published in the Journal of Pediatric Pharmacology and Therapeutics found that while propylene glycol is generally considered safe, toxicity can occur when used in high doses or for prolonged periods. Reported adverse effects from propylene glycol toxicity include central nervous system (CNS) toxicity, hyperosmolarity, hemolysis, cardiac arrhythmia, seizures, agitation, and lactic acidosis. Patients at risk for toxicity include infants, those with renal or hepatic insufficiency, epilepsy, and burn patients receiving extensive dermal applications of PG containing products.
- Study published in the European Journal of Gastroenterology & Hepatology in May 2016 found that high-volume polyethylene glycol bowel cleansing preparation has a long-lasting effect on the gut microbiota composition and homeostasis, with a decrease in the Lactobacillaceae abundance, a population of protective bacteria.
Feb 1999 – Approved by the FDA
February 18, 1999 – MiraLax approved by the FDA.
Jun 2008 – Study findings
June 2008 – Study finds that orally administered PEG-3350 is minimally absorbed, rapidly excreted and primarily eliminated via faeces.
2008 – FDA tests MiraLax
2008 – FDA tests 8 batches of MiraLax and finds the antifreeze ingredients ethylene glycol (EG) and diethylene glycol (DEG) in all batches.
Feb 2009 – Study findings
February 2009 – Study finds that mechanical bowel preparation products (MBP) like MiraLax offer no benefit as a preoperative colonoscopy measure.
Feb 2012 – PLOS ONE study findings
February 2012 – PLOS ONE study finds that standard bowel cleansing preparations alter the mucosal-adherent microbiota.
2012 – Empire State Consumer Project petition
2012 – Empire State Consumer Project (ESCP) petitions FDA to reopen its investigation into the safety of PEG 3350.
Oct 2014 – Study findings
October 2014 – Study finds that propylene glycol toxicity can occur when used in high doses or for prolonged periods.
2014 – Petition granted
2014 – FDA grants ESCP petition.
Jan 2015 – New York Times article
January 5, 2015 – New York Times article questions safety of laxative use in children.
Sep 2015 – FDA awards money for study
September 2015 – FDA awards $325,000 to the Children’s Hospital of Philadelphia (CHOP) to study effects of PEG 3350 laxatives on children.
- “Re: MiraLax (polyethlyene glycol 3350 NF Powder) NDA 20-698”. Department of Health & Human Services. March 1, 2001.
- “MiraLax Approval Package”. U.S. Food & Drug Administration (FDA). March 30, 2001.
- “Diethylene glycol poisoning”. Clinical Toxicology. July 2009.
- “Scrutiny for Laxatives as a Childhood Remedy”. The New York Times. January 5, 2015.
- “Polyethylene Glycol 3350”. MedlinePlus. March 15, 2016.
- “Ethylene Glycol Toxicity”. Medscape. June 24, 2016.