Breast feeding and epilepsy

Breast feeding is encouraged since all the older anti-epileptic drugs are only excreted in low concentrations - Phenytoin, carbamazepine and sodium valproate are only found in low concentrations in breast milk (1)

• blood levels of antiepileptic drugs in infants who are breast-fed are probably lower than in utero, but the possibility of sedation should be borne in mind in neonates of mothers taking carbamazepine, a benzodiazepine, phenobarbital or primidone (with respect to use of phenobarbital, fetal hepatic immaturity results in a considerable increase in its blood half life - up to 300 hrs)
  • if excessive sedation does occur then breast-feeding may need to be discontinued - however this step is rarely necessary
• there is little evidence about the safety of breast-feeding while using the newer antiepileptic drugs; many drug companies do not recommend breast-feeding while taking these drugs (1)
  
  
• a further review stated (2):
  • most studies on AED transfer through breastmilk report infant serum levels well below the limit of an expected pharmacological effect
  • some drugs have the potential to reach significant serum levels in breastfed infants, such as barbiturates, benzodiazepines, lamotrigine, and ethosuximide
  • breastfed infants should be monitored for side effects
  • adverse symptoms are rarely reported in breastfed infants of mothers taking AEDs, and prospective studies have failed to demonstrate any negative developmental effects in children that have been exposed to AEDs via breastmilk
  • the nursing infant's degree of drug exposure can be minimized by breastfeeding when drug concentrations in the milk are low, reducing maternal AED dosage to prepregnancy levels, and administering mixed nutrition
    
    
• levetiracetam and breast feeding (3)
  • a study showed that infant levetiracetam exposure via the breastmilk was close to the safety thresholds (trough breastmilk/serum ratio slightly below 1, relative infant dose (RID) >10% in fully breastfed infants), and the infant somnolescence reports could be related to exposure of the infants to levetiracetam via the breastmilk

Reference:

1. Drug and Therapeutics Bulletin 2005; 43(2):13-16.
2. Veiby G et al. Epilepsy and recommendations for breastfeeding. Seizure. 2015 May;28:57-65
3. Dinavitser N, Kohn E, Berlin M, Brandriss N, Bar-Chaim A, Keidar R, Livne A, Stepensky D, Berkovitch M, Sheinberg R. Levetiracetam in Lactation: How Much is Excreted into the Human Breast Milk? Br J Clin Pharmacol. 2021 Jun 15.