A breastfed child receives at most 1% of their mother’s dose when she uses oral medication. It is rarely recommended to avoid or stop breastfeeding, according to Caroline Morin and Ema Ferreira, pharmacists and researchers at the Research Centre of the CHU Ste-Justine.
Nevertheless, some drugs raise concern and that is why, for each patient, the doctor and pharmacist must take many factors into account before pronouncing their verdict.
Cons-indication: factors involved
- The dose ingested by the baby
The medication should not cause adverse effects if the amount to which the child is exposed is less than 10% of the pediatric dose. Pharmacists determine this amount by taking many factors into account such as the child’s weight. The pediatric dose is the dose that would be prescribed to the child if they took the drug for themselves.
- The ability of the baby’s body to maintain some internal characteristics (such as their temperature)
- The toxicity of the drug
- The age of the baby
Much of the antibodies are transmitted to the baby through breast milk during the first phase of breastfeeding. As the quantity of substances and nutrients coming directly from the mother is more important during this period, it is also the moment when your baby will be most exposed to the proteins of the drugs.
- The number of feedings and the average quantity consumed by the baby
- The prematurity of the baby
- The mother’s health
- The frequency of the drug intake
Likely side effects of medication during breastfeeding
There are very few studies on the long-term side effects of medication in breastfeeding women because the information is difficult to gather, says Ema Ferreira, who is also a teacher at the Université de Montréal.
However, we know that some drugs can disrupt the production of milk, either by reducing the production or ejection or by increasing it.
Other adverse reactions may include behavioral problems (lethargy, drowsiness, irritability, constant crying) and eating disorders (insufficient sucking, digestive problems) combined with slower weight gain, skin rash and an increased risk of infections.
The medication cannot be addictive for children except if the mother consumes methadone (a heroin substitute prescribed during withdrawal) during pregnancy: the baby could experience methadone withdrawal.
Over the counter and safe medicine
- Aspirin: must be taken moderately
- Ibuprofen (Advil for example) and other anti-inflammatory drugs
- Pain relievers (Tylenol for example).
- Antihistamines (for allergies): Claritin brand is not cons-indicated but it is best to consult a pharmacist before choosing a brand.
- Antitussive (Cough and sore throat syrups).
- Drugs that relieve nasal congestion: some may decrease milk production.
- Birth control pill: could decrease the production of milk if taken too early after childbirth.
Drugs that are always or often cons-indicated
- Antibiotics: very little are cons-indicated while others must be used with precaution and monitored by a doctor.
- Antidepressants: some of them have no effect while others require a close monitoring of the baby.
- Lithium (for bipolar disorder): should only be prescribed to stable and reliable women and any signs of lethargy, suction decrease and hypotonia (decreased muscle tone) in the baby must be reported to a doctor.
- Anticonvulsants: some of them cause little exposure while others may cause medium to high exposure in the infant.
- Antihistamines: only certain brands.
- Sedatives and sleeping pills: taken in strong doses, it can cause drowsiness in the baby.
- Beta-blockers (for heart problems): some can be used while others raise concerns.
- Cancer drugs: usually cons-indicated.
- Narcotics: usually cons-indicated.
Breastfeeding on medication: warnings
- Do not self-medicate. Consult your doctor or your pharmacist and avoid combining drugs.
- Your doctor should only treat you if it is truly necessary and avoid prescribing “comfort” drugs.
- Take your medication just after feeding or schedule the feedings so that your child doesn’t drink when the drugs are peaking.
- Mothers of premature babies should be even more careful.