Who can use antihistamines 

Most people are able to take antihistamines. However, antihistamines are not recommended in certain circumstances.

These are explained below.

Health conditions

A number of health conditions can be made worse by taking antihistamines, or they can cause the antihistamines to react unpredictably. These include:

Before taking antihistamines, seek advice from your GP or pharmacist if you have another health condition and you are unsure whether antihistamines are suitable for you.


As a general rule, avoid taking any medication during pregnancy unless there's a clear clinical need. Always check with your GP, pharmacist or midwife before taking any medication.

If you're pregnant and feel that you need antihistamines, your healthcare professional may first recommend nasal sprays, nose drops or eye drops.

If these do not work, they may recommend an oral antihistamine, usually loratadine or cetirizine.

Chlorphenamine is also considered safe to use during pregnancy, but should be avoided close to labour and childbirth as it can cause problems in the baby, such as irritability or tremor (shaking).

Read more information about taking hay fever medication during pregnancy.


It may be possible for you to take some hay fever medicines while you're breastfeeding without risk to your baby. 

However, you should always get advice from your pharmacist, GP or health visitor first. They will take into account factors such as:

  • how mild or severe your symptoms are - if your symptoms are mild, you may be able to manage without treatment
  • how effective the medicine is
  • how much of the medicine passes to your baby through your breast milk 

Read more information about taking hay fever medication while breastfeeding.


Some antihistamines, such as alimemazine and promethazine, aren't suitable for children under two years old. You should seek advice from your GP if your child is under two years old and you think they require treatment with antihistamines.

Some antihistamines are not recommended for children with certain conditions. For example, the National Institute for Health and Care Excellence (NICE) recommends that oral antihistamines are not used routinely to treat children with atopic eczema.

Before giving your child any form of medication, always read the patient information leaflet for advice about whether the medication is suitable for them.

Page last reviewed: 10/01/2013

Next review due: 10/01/2015