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THE SAFETY OF PERMETHRIN DURING PREGNANCY OR BREASTFEEDING

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.

THIS MEDICATION IS UNLIKELY TO CAUSE HARM TO YOUR BABY:

Permethrin is considered safe for treating lice or scabies during pregnancy. Available human studies suggest there is no increased risk of harm to the baby with short-term use of permethrin during pregnancy or breastfeeding.

What is permethrin?

Permethrin is a medication that is taken to control the symptoms of a parasitic infection. Permethrin is currently available as either a generic or brand name medication. Brand names of permethrin include Elimite™ and Acticin™. Nix™ is a permethrin cream rinse available over the counter. Permethrin is available as a topical cream and is applied once (a second application may be required if mites or lice are still present 1-2 weeks after the first application). It is available by prescription from your doctor and over the counter. 

What is permethrin used to treat?

Permethrin is used to treat head lice and scabies in infants over 2 months old, children, adolescents, and adults. Scabies is a parasitic infection of the skin that is common in developing countries and low-income communities. In scabies, mites cause inflammation and irritation of the skin. Scabies can spread through person-to-person contact or contact with items from an infected person. Head lice is a parasitic infection that also spreads person-to-person and causes itching and inflammation. 

How does permethrin work?

Permethrin works by interfering with nerve impulses in parasites, leading to paralysis of the parasite and death.

If I am taking permethrin, can it harm my baby?

The CDC considers permethrin the preferred treatment for pubic lice and scabies during pregnancy and while breastfeeding a baby. Studies have not shown an increased risk of harm with this medication during pregnancy. It is estimated that less than 2% of permethrin cream is absorbed into the body after being applied to the skin surface. Short-term use of topical permethrin is not expected to pose significant harm to a baby. 

Evidence from animal atudies with permethrin:

Animal studies have not shown a risk of harm to the baby with permethrin exposure during pregnancy. When given orally to pregnant mice, rats, and rabbits, there was no harm reported.  Mice exposed to permethrin had an increased risk of cancer, but this was not true for rats.

Evidence for the risks of permethrin in human babies:

A study published in 2005 evaluated the safety of permethrin in 113 pregnant women compared to 113 pregnant women not exposed to permethrin. There were no differences in miscarriages, birth weight, birth defects, live births, or gestational ages between women exposed versus not exposed to permethrin. A study in low-income areas of New York City found that pregnant women exposed to environmental pesticides containing permethrin during the third trimester of pregnancy were not at an increased risk of having babies with neurodevelopmental problems at 36 months old; however, exposure to another chemical, piperonyl butoxide, was associated with neurodevelopmental problems in babies. A Thai study found no difference in rates of miscarriages, death, birth defects, stillbirth, premature delivery, birthweight, or gestational age in pregnant women exposed to permethrin versus pregnant women not exposed to this medication. 

Bottom line: Permethrin is considered compatible with pregnancy. Human studies have not shown an increased risk of adverse events or birth defects in babies exposed to this medication during pregnancy.

If I am taking permethrin and become pregnant, what should I do?

If you are taking permethrin and become pregnant, you should contact your doctor immediately. Your doctor will determine if your medication is medically necessary, or if it should be discontinued until after the birth of your baby.

If I am taking permethrin, can I safely breastfeed my baby?

It is unknown if permethrin passes into the breast milk with topical exposure. Environmental exposure to permethrin through malaria treatment or agricultural use has been documented to pass into breast milk and poses unknown long-term health concerns. There are five case reports of nursing infants exposed to permethrin and no adverse events were reported. The CDC and the World Health Organization consider permethrin safe in women who are breastfeeding a baby. The manufacturer of permethrin recommends avoiding breastfeeding while on this medication. 

Bottom line: Permethrin is considered compatible with breastfeeding. It is not known if permethrin passes into breast milk, but topical application of this medication is not expected to be readily absorbed into the body.

If I am taking permethrin, will it be more difficult to get pregnant?

Studies in animals suggest there is no risk of adverse effects on fertility with permethrin use. 

If I am taking permethrin, what should I know?

The CDC considers permethrin safe for treating pubic lice and scabies during pregnancy and while breastfeeding. No human studies have shown an increased risk of harm to the baby with use of this medication.

If I am taking any medication, what should I know?

This report provides a summary of available information about the use of permethrin during pregnancy and breastfeeding. Content is from the product label unless otherwise indicated.

You may find Pregistry's expert report about scabies and lice here .   Additional information can also be found in the resources below. 

For more information about permethrin, scabies, and lice during and after pregnancy, contact http://www.womenshealth.gov/ (800-994-9662 [TDD: 888-220-5446]) or check the following links:

World Health Organization: Scabies

Medline Plus: Head lice

U.S. National Library of Medicine: LACTMED: PERMETHRIN 

Read the whole report
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.