Can I take chlorphenamine while pregnant or breastfeeding?
A plain-words look at what the NHS, the US drug label and LactMed say about chlorphenamine.
In short
Pregnancy: You can take chlorphenamine in pregnancy.
Breastfeeding: You can take chlorphenamine during breastfeeding if your baby is healthy, although an antihistamine that doesn't cause drowsiness might be better. Speak to your doctor or pharmacist first, and they will help you decide.
Your doctor, midwife or pharmacist can help you decide.
What this means for you
Pregnancy
- There's no good evidence that it harms your baby, although it can make you drowsy, among other side effects.
- Your doctor or pharmacist may suggest an antihistamine that doesn't make you drowsy (such as loratadine) instead of chlorphenamine.
Breastfeeding
- You can take chlorphenamine during breastfeeding if your baby is healthy, although an antihistamine that doesn't cause drowsiness might be better.
- Speak to your doctor or pharmacist first, and they will help you decide.
- The amount of chlorphenamine that reaches breast milk is not known, but the levels are probably low.
- Breastfeeding mothers have used it widely for many years without it causing side effects in babies.
- However, as it could make your baby sleepy, it's better to take it only now and then or for a short time.
- Side effects in breastfed babies from medicines their mother takes are very rare, but it's important to keep an eye on your baby whenever you take a medicine while breastfeeding.
- Carry on breastfeeding as normal until you've had advice about your baby's symptoms.
- It's important that you do not share a bed with your baby while taking chlorphenamine.
When to get help
- Contact a healthcare professional or call 111 (NHS 111 in the UK) as soon as you can if your baby is feeding less well than normal, seems unusually sleepy, or seems unusually irritable.
- For symptoms not mentioned here, or if you're worried about your baby, you can also speak to any healthcare professional or call 111.
Talk to your doctor or pharmacist
This page is educational, not advice for your own situation. Talk to your doctor, midwife or pharmacist before you start, stop or change any medicine in pregnancy or while breastfeeding.
The details: what each source says
Chlorphenamine in pregnancy
The NHS says
You can take chlorphenamine in pregnancy. There's no good evidence that it harms your baby, although it can make you drowsy, among other side effects.
Your doctor or pharmacist may suggest an antihistamine that doesn't make you drowsy (such as loratadine) instead of chlorphenamine.
In our words, from the NHS page Chlorphenamine (Piriton) (nhs.uk). Contains public sector information licensed under the Open Government Licence v3.0 (OGL v3.0). The NHS does not endorse this site.
The US Drug Facts label says
If pregnant or breast-feeding, ask a health professional before use.
Drug Facts label: Allergy Relief (oral), WALMART INC. Label on DailyMed. Quoted verbatim; US labels are written for US prescribers and patients.
Chlorphenamine while breastfeeding
The NHS says
You can take chlorphenamine during breastfeeding if your baby is healthy, although an antihistamine that doesn't cause drowsiness might be better. Speak to your doctor or pharmacist first, and they will help you decide.
The amount of chlorphenamine that reaches breast milk is not known, but the levels are probably low. Breastfeeding mothers have used it widely for many years without it causing side effects in babies. However, as it could make your baby sleepy, it's better to take it only now and then or for a short time.
Side effects in breastfed babies from medicines their mother takes are very rare, but it's important to keep an eye on your baby whenever you take a medicine while breastfeeding.
Contact a healthcare professional or call 111 (NHS 111 in the UK) as soon as you can if your baby is feeding less well than normal, seems unusually sleepy, or seems unusually irritable.
For symptoms not mentioned here, or if you're worried about your baby, you can also speak to any healthcare professional or call 111.
Carry on breastfeeding as normal until you've had advice about your baby's symptoms.
It's important that you do not share a bed with your baby while taking chlorphenamine.
In our words, from the NHS page Chlorphenamine (Piriton) (nhs.uk). Contains public sector information licensed under the Open Government Licence v3.0 (OGL v3.0). The NHS does not endorse this site.
LactMed says
Small (2 to 4 mg), occasional doses of chlorpheniramine are acceptable during breastfeeding. Larger doses or more prolonged use might cause effects in the infant or decrease the milk supply, particularly in combination with a sympathomimetic such as pseudoephedrine or before lactation is well established. Single bedtime doses after the last feeding of the day may be adequate for many women and will minimize any effects of the drug. The nonsedating antihistamines are preferred alternatives, though.
“Summary of Use during Lactation”, LactMed record “Chlorpheniramine” (LM64), quoted verbatim. Everything LactMed reports about Chlorpheniramine while breastfeeding.
Other names
UK brand names (per the NHS): Piriton, Allerief, Pollenase.
Indian combination brands that include chlorphenamine: Sinarest.
US name: chlorpheniramine.
Sources
- NHS, Chlorphenamine (Piriton) (nhs.uk), page last reviewed 14 May 2025. Paraphrased. Contains public sector information licensed under the Open Government Licence v3.0.
- US drug label: Allergy Relief (oral), WALMART INC., human otc drug, label effective 31 August 2026, set ID 5e6623c3-6210-4c50-94d6-5554f36876d1. DailyMed (National Library of Medicine). Public domain; quoted verbatim.
- Drugs and Lactation Database (LactMed), National Institute of Child Health and Human Development (NICHD), via NCBI Bookshelf, record “Chlorpheniramine” (LM64), bulk release of 22 September 2026. LactMed on NCBI Bookshelf. Public domain; quoted verbatim. LactMed is a registered trademark of the U.S. Department of Health and Human Services.
Sources checked 26 September 2026. How we source and check every page.
Educational summary of named sources, not medical advice.