Permethrin

(Date: December 2013. Version: 2.1)

This factsheet has been written for members of the public by the UK Teratology Information Service (UKTIS). UKTIS is a not-for-profit organisation funded by Public Health England on behalf of UK Health Departments. UKTIS has been providing scientific information to health care providers since 1983 on the effects that medicines, recreational drugs and chemicals may have on the developing baby during pregnancy.

What is scabies?

Scabies is a skin condition caused by a type of tiny insect or ‘mite’ that burrows into the skin causing intense itching which is worse at night.

Scabies is very contagious and is spread by skin-to-skin contact with an infected person or through contact with contaminated items such as clothing or bedding.

If you are pregnant and think you have scabies you should ask your GP for advice.

How is scabies treated during pregnancy?

There are no official guidelines as to how scabies should be treated in pregnancy. Two different insecticides (chemicals that kill insects), permethrin (Lyclear® Dermal Cream) and malathion (Derbac® M Liquid, Prioderm® Lotion), are available in the UK for treating scabies. They work by poisoning the scabies mite.

Use of permethrin and malathion in pregnancy is not known to cause problems for the unborn baby, but their use has not been well studied in pregnancy. The limited scientific information that is available for these two insecticides is summarised below.

Permethrin

Can using permethrin in pregnancy cause my baby to be born with birth defects?

Studies of small numbers of women have not shown that using permethrin during pregnancy increases the risk of having a baby with a birth defect. 

Can using permethrin in pregnancy cause miscarriage?

No evidence that women who use permethrin during pregnancy have a higher chance of having a miscarriage was provided by either of the two studies that have investigated this. 

Can using permethrin in pregnancy cause preterm birth or my baby to be small at birth (low birth weight)?

No link between permethrin use during pregnancy and giving birth before 37 weeks of pregnancy or having a baby with a low birth weight (<2500g) was shown in the two studies which investigated this. 

Can using permethrin in pregnancy cause stillbirth?

No increased risk of stillbirth has been shown in women who use permethrin during pregnancy.

Can using permethrin in pregnancy cause other health problems or problems with learning and behaviour in the child?

No studies have been carried out to look at whether there is an increased risk of other health, learning or behavioural problems in children whose mothers used permethrin while pregnant.

Malathion

The manufacturers of malathion state that pregnant women should consult their doctor before use.

Although no studies have been carried out to look at whether applying malathion to the skin to treat scabies during pregnancy is linked to an increased risk of poor pregnancy outcome or problems as the child gets older, a small number of studies have looked at the pregnancy outcomes of women who have been exposed to malathion in crop sprays, either through their work (on farms for example) or because they live in an area where crop spraying occurs.

Most studies of women exposed to malathion in crop sprays show that they are not at an increased risk of having a miscarriage, a baby with a birth defect, a premature delivery (born before 37 weeks of pregnancy), a baby with a low birth weight (<2500g), or of children who were exposed in the womb having behavioural or learning difficulties when they get older. We do not know how this information relates to using malathion to treat scabies.

What if I have to treat my child’s scabies and I am pregnant?

If you do not require treatment for scabies yourself, but need to apply insecticides to another family member, it is recommended that you follow the manufacturer’s instructions to avoid exposing yourself to chemicals unnecessarily.

Will my baby need extra monitoring during pregnancy?

Using treatments for scabies during pregnancy is not expected to cause any problems that would require extra monitoring of your baby.

Are there any risks to my baby if the father has used scabies treatments?

We would not expect any increased risk to your baby if the father used scabies treatments before or around the time your baby was conceived.

Who can I talk to if I have questions?

If you have any questions regarding the information in this leaflet please discuss them with your health care provider. They can access more detailed medical and scientific information from www.uktis.org.  

General information 

Up to 1 out of every 5 pregnancies ends in a miscarriage, and 1 in 40 babies are born with a birth defect. These are referred to as the background population risks.  They describe the chance of these events happening for any pregnancy before taking factors such as the mother’s health during pregnancy, her lifestyle, medicines she takes and the genetic make up of her and the baby’s father into account.

Medicines use in pregnancy

Most medicines used by the mother will cross the placenta and reach the baby. Sometimes this may have beneficial effects for the baby.  There are, however, some medicines that can harm a baby’s normal development.  How a medicine affects a baby may depend on the stage of pregnancy when the medicine is taken. If you are on regular medication you should discuss these effects with your doctor/health care team before becoming pregnant.

If a new medicine is suggested for you during pregnancy, please ensure the doctor or health care professional treating you is aware of your pregnancy.

When deciding whether or not to use a medicine in pregnancy you need to weigh up how the medicine might improve your and/or your unborn baby’s health against any possible problems that the drug may cause. Our bumps leaflets are written to provide you with a summary of what is known about use of a specific medicine in pregnancy so that you can decide together with your health care provider what is best for you and your baby.   

Every pregnancy is unique. The decision to start, stop, continue or change a prescribed medicine before or during pregnancy should be made in consultation with your health care provider. It is very helpful if you can record all your medication taken in pregnancy in your hand held maternity records.

   

www.medicinesinpregnancy.org

Disclaimer: This information is not intended to replace the individual care and advice of your health care provider. New information is continually becoming available. Whilst every effort will be made to ensure that this information is accurate and up to date at the time of publication, we cannot cover every eventuality and the information providers cannot be held responsible for any adverse outcomes following decisions made on the basis of this information. We strongly advise that printouts should NOT be kept for any length of time, or for “future reference” as they can rapidly become out of date.

My bump’s record

Create your own ‘My bump’s record’.

Provide information about your pregnancy to help women in the future. 

Login to my bumps

Join my bumps