Medicines to avoid while breastfeeding

Glass of water and two pillsIs it necessary to remain completely medication-free when you are breastfeeding? What about in hayfever season? Or when you are feeling lousy with a pesky cold or the flu? What about the pill, or antidepressants?

The good news is there are medicines you can take when breastfeeding. It's not always necessary to suffer in silence (or even while moaning loudly).

Most over-the-counter medicines will advise caution when breastfeeding, mainly because they have not been specifically licensed for breastfeeding women. This will often be because there has not been enough research into the effects of the medicine on breastfed babies. The Breastfeeding Network says that some of these warnings can be based on just one report of an adverse reaction.

If in doubt, it's best to talk to your doctor (and always to make them aware that you're breastfeeding when they prescribe you anything). In general though, if you can avoid taking a drug, it is best to do so.

Medicines do pass to your baby via your breast milk - about 1% of a drug. But this doesn't necessarily mean they will do your baby any harm. You have to weigh up the benefits of taking the drug for your own health versus the possible risk of any damage to your baby, however slight. Again, discuss it with your GP if you need more information.

Before taking any medication while breastfeeding consider:

  • How old your baby is and whether they were born prematurely. The liver and kidneys of younger babies are still developing and are less likely to cope with any harmful effects of any drugs.
  • Whether your baby is breastfeeding exclusively or also taking solids and and having less frequent feeds - this will lessen the impact of any drug.
  • Any research into the safety of the particular drug.
  • The benefits of taking the drug: do you really need to take it and are there any alternatives you could try?

If you take medicine while breastfeeding try to:

  • Choose single-ingredient options rather than ones that cram a variety of active ingredients into one pill.
  • Take your medication after feeding and try to leave two to hours hours before feeding again.
  • Use drops and sprays rather than pills and choose non-drowsy options to avoid any unnecessary adverse risks.

What common over-the-counter drugs should be avoided while breastfeeding?

  • Aspirin (because of an increased risk of Reye's syndrome)
  • Codeine (as it can cause sedation)
  • Pseudoephedrine - a decongestant that can reduce milk supply
  • Phenylephrine and phenylpropanolamine - both decongestants found in some cold medicines
  • Guaifenesin: an expectorant (to bring up phlegm) found in some cough medicines
  • Medicines that may cause drowsiness

Explore alternatives. There are safe painkillers you can take and you can find softer options for coughs and colds. Kellymom has information on cold and allergy remedies compatible with breastfeeding.

Recreational drugs should be avoided as they can have a negative impact on your baby and may make you less able to look after your child. There have been some studies into the effect of cannabis passed on through breastmilk that suggest it could effect a child's motor skills development at one year. The research isn't extensive, but why risk it?

What medicines are OK to take while breastfeeding?

  • Most antibiotics
  • Painkillers such as paracetamol and ibuprofen (but not aspirin)
  • Hayfever medicines (choose non-sedating antihistamines)
  • Cough medicines - linctus is fine but decongestants should be avoided as they can greatly reduce your milk supply
  • Asthma inhalers
  • Normal doses of vitamins but not the mega-level vitamins
  • Most antidepressants are OK to take, but check with your GP first
  • Anticoagulants for DVT
  • Domperidone, but only in low doses
  • The flu jab and other immunisations will also benefit your baby
  • Corticosteroid injections
  • Drugs that have also been formulated for children are usually safe for breastfeeding mums; this includes loratadine and cetirizine for hayfever
  • Warfarin and Heparin anticoagulants are protein-bound in the blood and so less likely to enter breastmilk (but if you need to take these drugs make sure your baby has vitamin K at birth, as the anticoagulants may deplete your milk supply)

What about the pill?

Not all contraceptive pills are recommended while you're breastfeeding, especially those that contain oestrogen. Check with your GP which ones are safe to take.

Don't believe the 'you can't get pregnant while breastfeeding' myth. Oh and if you should need to, it is possible to take the morning-after pill without stopping breastfeeding.

Useful resources

  • The Breastfeeding Network has  detailed factsheets about medications and lactation.
  • Toxnet has a database of evidence about drugs and lactation and a free app called Lactmed, which provides information on medicines from the National Library of Medicine in the US.

What Mumsnetters say about medicines and breastfeeding

  • Don't just take stuff willy-nilly, make sure you get some information from reliable resources if you're not sure. 
Decongestants are generally a no-go as they can reduce milk supply. Lots of other things are OK. I've learnt a lot through having flu, have spent many hours in front of the open bathroom cabinet, hammering away at my Lactmed app hoping it would say yes. EauRouge
  • The combined pill can interfere with milk production but you can take the mini-pill whilst breastfeeding. TheHouseofMirth


Image: Shutterstock

Last updated: 9 months ago