MiraLAX Explained: Usage, Dosage, And Side Effects

Constipation is awkward to talk about, but even more awkward to live with. If you experience it, you know it probably won't kill you, but you'll certainly want to get it over with as quickly, safely, and comfortably as possible. And since it was approved for over-the-counter use by the FDA in 2006 (per ABC 7), MiraLAX — a brand of laxative featuring the active ingredient polyethylene glycol 3350 — has become a popular option for those seeking relief from constipation.

Indeed, in the years after its introduction, MiraLAX became so trusted by consumers and doctors that both began administering it for off-label purposes for which it had not been studied or tested, such as treating chronic constipation in children, according to The New York Times. This widespread off-label usage, along with reports of MiraLAX's dangerous side effects in some children, made the medication the center of controversy. But after subsequent study (per the University of Rochester Medical Center), the controversy and concerns about its risks seem to have subsided, and MiraLAX continues to be a popular option for those dealing with occasional constipation. Here's what you need to know about MiraLAX and how it works.

While most over-the-counter laxatives and safe and effective when taken properly, overusing them — or using stronger laxatives than you need — can make your problems even worse, according to Harvard Health Publishing. Using strong laxatives over a prolonged period of time, for example, can cause your body to become so dependent on them you won't be able to pass a bowel movement without them — not a good situation.

Instead, Harvard Health Publishing recommends you start with the gentlest, most conservative laxative option: bulk-forming fiber-based products such as Metamucil. While these are safe enough to take daily, they need some time to take effect — up to three days for some people. If this doesn't offer the relief you want, try mineral oil or a stool softener such as Correctol (one or the other, not both at the same time). And only if you're still not seeing any effects with these should you move on to trying osmotic laxatives such as MiraLAX. If your condition persists despite trying a number of different medications, it's time to see your doctor.

For a while, MiraLAX was making headlines for all the wrong reasons. As its popularity as an over-the-counter laxative grew, so did its off-label use as a treatment for children with constipation. At the time, as ABC 7 notes, the FDA had only authorized MiraLAX for adult use. Despite this restriction, however, it became a go-to solution for both parents and doctors trying to treat constipation in children. This unauthorized use of the medication was so common that a 2006 study found that in a nationwide sample of 350 pediatricians, 75% had recommended MiraLAX for constipation in children, according to The New York Times.

But some parents, however, noted some disturbing changes in their children's behavior after giving them MiraLAX. Normally cheerful children suddenly became paranoid, angry, and erratic after taking MiraLAX, per ABC 7. Terrified parents demanded the FDA take action, and in response, the FDA launched a study to investigate the effects of the active ingredients in MiraLAX on children. Preliminary findings revealed no meaningful connection between MiraLAX and behavioral or neurological changes, according to the University of Rochester Medical Center, and doctors continued to recommend MiraLAX for pediatric patients.

MiraLAX was originally marketed as a treatment for occasional constipation in adults, something that's safe and easy to take on those rare occasions your system is feeling a bit out of balance. Since then, doctors have administered it in a number of other ways, with the size and frequency of the dose varying with the patient and the targeted outcome. For instance, small doses of MiraLAX are often used to help develop and maintain regularity in children with chronic constipation problems, according to UCSF Pediatric Urology.

In these cases, MiraLAX serves not only to ensure the child being treated has regular bowel movements, but helps retrain the child's body to stay regular on its own. In chronically constipated children, the rectum stretches to accommodate accumulated stools, causing affected children to lose their ability to sense when their bowels are full. Regular doses of MiraLAX help keep the bowels relatively empty so the child's system relearns to recognize when they are full and need to be emptied. As the child starts to become more regular, doses of MiraLAX can be gradually decreased. Children will typically require maintenance doses of MiraLAX for one to three months.

While medications can be beneficial when used correctly for their intended purpose, not all medications play well with each other. As the Mayo Clinic explains, some drugs interact in harmful ways with other medications, causing unpleasant or unsafe side effects or negating the effectiveness of one or both medications. This is why your doctor will ask about any medications you're currently taking before prescribing a new one.

Luckily, MiraLAX has been found to interact negatively with only a handful of other medications, all of which are stimulant laxatives — bisacodyl, licorice, senna, and sodium picosulfate. And as noted by Harvard Health Publishing, it's generally not wise to self-medicate with more than one type of laxative at a time in any case (although for certain procedures, such as colonoscopy prep, more than one type may be recommended, per the Cleveland Clinic). In addition, Michigan Medicine advises against taking other medications at the same time that you take MiraLAX, since MiraLAX may keep them from being properly absorbed by your body.

Pregnancy can be a joyous time of one's life, but it can also be uncomfortable at times. And part of the price you may have to pay to bring your little bundle of joy into the world is constipation: Hormonal changes, the growing fetus pressing against your bowels, and even the iron in your prenatal vitamins can all contribute to the problem, according to the Cleveland Clinic. And while you may be desperate for relief, you may also be understandably concerned about your baby's safety. Would the laxatives you normally take, such as MiraLAX, be safe to take now?

Fortunately, the answer is yes: According to the University of California Irvine School of Pharmacy and Pharmaceutical Sciences, the American Gastroenterological Association has determined that MiraLAX is safe for use during pregnancy. Still, the Cleveland Clinic reminds us that the best and safest way to address pregnancy-related constipation is not to get constipated in the first place. They recommend proactively taking preventative measures — such as drinking plenty of water and adding fiber to your diet — to keep yourself regular during pregnancy.