The information provided below is for readers based in the United States of America. Readers outside of the United States of America should seek the information from local sources.

What is loperamide?

Loperamide is an opioid drug that is used widely to treat diarrhea, both chronic (long-term) and acute (intense episode with a rapid onset). By binding to a type of opioid receptor called the mu receptor, loperamide reduces the intensity and frequency of the contraction of the muscles in the wall of the intestines, resulting in a slowing of the movement of feces. At dosage levels needed to slow intestinal activity, loperamide does not absorb significantly into the blood stream. Consequently, the drug does not require a prescription and traditionally has not been considered to have abuse potential. Beginning in the mid 2010s, however, physicians and researchers began realizing that people were abusing loperamide by taking it in very high quantities – quantities far beyond the recommended 2-4 mg per dose, 8 mg maximum per day if you obtain the drug over-the-counter (16 mg per day is permitted with a prescription). This results in the drug entering the bloodstream and central nervous system enough to produce euphoria, a high like one gets from other opioid drugs.

Is there a safe level of loperamide that I can use during pregnancy?

Yes. The whole point of loperamide is that you take it at a dose that is too low to penetrate from the gastrointestinal tract to the body. Loperamide is appropriate for treatment of diarrhea, which can often develop in pregnancy with irritable bowel syndrome, although it could also be part of a more serious conditions such as food poisoning, so you should consult with your physician, at least by phone. If you have diarrhea, a starting dose of up to 4 mg (two tablets) is acceptable, followed by doses of 2mg (1 tablet) as needed up to a maximum of 8 mg per day (16 mg per day is permitted with a prescription). If you still need loperamide after two days, you should visit your physician.

Can loperamide make it harder for me to get pregnant?

Although this has not been investigated in humans adequately to determine the presence or absence of an effect on fertility, results from studies conducted on rodents suggest strongly that fertility effects depend on dosage. If you take loperamide at the dosage recommended for treatment of diarrhea, it should not make it harder for you to get pregnant. On the other hand, if you take loperamide at many times the recommended dosage, there is good reason to think that it would be harder for you to get pregnant. The same is true if your male partner takes loperamide many times beyond the recommended dose. Fertility is not the only problem associated with loperamide abuse. Along with the euphoric effects in the brain that lead to addiction, high dose loperamide will cause severe constipation. Additionally, the drug affects muscle cells in ways that lead to abnormalities in the electrical activity and rhythm of the heart. Such changes can lead to recurrent loss of consciousness, cardiac arrest (the heart stops), and death.

Can loperamide cause a miscarriage?

Loperamide is not known to cause spontaneous abortion (miscarriage).

Can loperamide use during my pregnancy cause a birth defect?

Some uncertainty surrounds this issue as there have been studies suggesting a modest risk of birth defects connected with loperamide. Such research is based on a low number of cases, however, and conflicts with other study results suggesting that there is no danger of birth defects. Larger studies are needed to make it clear whether loperamide causes birth defects. If you suffer from a bout of diarrhea, only a few small doses of loperamide are needed so it is unlikely that it would harm your baby.

Are there long-term consequences to my baby from my loperamide use?

As noted above, there have been studies suggesting a modest risk of birth defects connected with loperamide. However, such research is based on a low number of cases and conflicts with other study results suggesting that there is no danger of birth defects. Larger studies are needed.

I just found out I am 6 weeks pregnant and last weekend I used loperamide. Will my baby have a problem?

If you took the recommended dose of loperamide to treat diarrhea, it is very unlikely that this will harm your baby. On the other hand, if you took excessive amounts of loperamide as part of a pattern of loperamide abuse, it’s possible that the baby may suffer damage. If this is the case, then you could be harmed as well, since high doses of loperamide can lead to problems in the heart and other organs.

Is binge use of loperamide on only some days of the week as risky as using loperamide everyday but at lower amounts?

Taking high doses (binges) of loperamide on some days of the week is MORE risky than using loperamide every day at the recommended dose of no more than 8 mg per day. As noted in other sections, the recommended dose is not risky for you, and probably not for your baby either, but you should consult your physician if you find that you need to take loperamide for more than two days to counter diarrhea.

Is it ok to use loperamide after the first trimester?

If your use of loperamide is limited to the recommended dosage and limited to a couple of days for the purpose of treating diarrhea, loparamide is not likely to do harm, regardless of whether or not it is early in pregnancy. However, you should inform your physician of your condition, as there are many potential reasons why loperamide may not be the best treatment for whatever is the underlying reason for your diarrhea.

Can a baby go through loperamide withdrawal after birth?

If you take only the recommended dosage of loperamide, withdrawal in the newborn is extremely unlikely, since you would not build up the drug in your bloodstream, and it therefore would not reach the developing baby, even if higher doses of the drug could penetrate the placenta (an issue that is not resolved). On the other hand, if you abuse loperamide by taking high doses, withdrawal is quite possible after the baby is born.

How will I know if loperamide has hurt my baby?

It would be hard to know, since every pregnancy begins with a 2 – 3.5 percent chance of a birth defect, independent of any drug use. However, if you take loperamide at the recommended dosage for treatment of diarrhea, you can be very confident that it is not the reason for any problems that your baby might suffer.

Is there any hope for a baby who has been exposed to loperamide throughout pregnancy?

Yes. There are many uncertainties regarding the long term effects of loperamide on the developing baby, but there are treatments available in the event that a newborn suffers from withdrawal as a result of the mother abusing the drug to the point that significant levels did reach the baby.

Can I use loperamide while breastfeeding?

Loperamide is thought to be safe in breast feeding mothers, if taken in recommended doses.

What if the father of the baby uses loperamide prior to conception?

Paternal use of loperamide is not thought to cause birth defects. However, rodent studies hint that taking loperamide at doses far in excess of the dose recommended for diarrhea treatment can have a negative impact on the fertility of your male partner, making it difficult to get pregnant in the first place.

Resources for loperamide use in pregnancy:

For more information about loperamide during pregnancy, contact (800-994-9662 [TDD: 888-220-5446] or contact the following organizations:

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Last Updated: 22-03-2019
General information

It is very common for women to worry about having a miscarriage or giving birth to a child with a birth defect while they are pregnant. Many decisions that women make about their health during pregnancy are made with these concerns in mind.

For many women these concerns are very real. As many as 1 in 5 pregnancies end in a miscarriage, and 1 in 33 babies are born with a birth defect. These rates are considered the background population risk, which means they do not take into consideration anything about the health of the mom, the medications she is taking, or the family history of the mom or the baby’s dad. A number of different things can increase these risks, including taking certain medications during pregnancy.

It is known that most medications, including over-the-counter medications, taken during pregnancy do get passed on to the baby. Fortunately, most medicines are not harmful to the baby and can be safely taken during pregnancy. But there are some that are known to be harmful to a baby’s normal development and growth, especially when they are taken during certain times of the pregnancy. Because of this, it is important to talk with your doctor or midwife about any medications you are taking, ideally before you even try to get pregnant.

If a doctor other than the one caring for your pregnancy recommends that you start a new medicine while you are pregnant, it is important that you let them know you are pregnant.

If you do need to take a new medication while pregnant, it is important to discuss the possible risks the medicine may pose on your pregnancy with your doctor or midwife. They can help you understand the benefits and the risks of taking the medicine.

Ultimately, the decision to start, stop, or change medications during pregnancy is up to you to make, along with input from your doctor or midwife. If you do take medications during pregnancy, be sure to keep track of all the medications you are taking.