Patient: My package of hayfever relief antihistamine 15 mg says I should not take it if I am pregnant or breastfeeding. There is a very slight chance that I am pregnant. Does this mean I should not take the antihistamine?
Doctor: The hay fever relief tablets that you refer to contains 15 mg of loratadine.Loratadine is one of the newer antihistami nes, which seems to be less likely to cause drowsiness than older antihistamines. The caution on the box is one given with all antihistamine medication. This relates to the fact that there is insufficient evidence to state that these drugs are safe to be used in pregnancy. However there is no evidence that antihistamine medication used in early pregnancy causes abnormalities in the foetus. In later pregnancy it is thought that high doses may have toxic effects. Medication should be used in pregnancy only when the benefit to the mother is thought to be greater than the risk to the foetus, and this is especially important from week three until week 11. Later on in pregnancy medication may affect the growth of the foetus or have other toxic effects. It is very unlikely that taking loratadine at a dose of 15 mg daily would have any harmful effects upon a developing foetus, but the drug is not safe beyond all doubt. One alternative would be for you to use antihistamine eye drops and nasal spray rather than an oral medication.