For babies exposed to some drugs in the womb, there can be a difficult period for them in the first week before they adapt to exposure to a lower level of the drug (e.g., anti-depressant medication) in their mother’s breastmilk. Some authorities suggest that mothers who have taken these drugs should remain in hospital in order to keep the baby under observation; others do not.

Anti-depressants

If you have taken fluoxetine, venlafaxine and paroxetine in pregnancy, I recommend that you discuss hand expression with your midwife during an antenatal appointment. Your baby may be sleepier than other babies as they withdraw from the drug.

Hand expressing or expressing your breast milk if your baby is sleepy and hard to rouse you can stimulate your milk supply and feeding expressed milk can help to keep your baby’s blood sugars up, reducing the risk of it being suggested that you top up with formula milk. It would also be useful to have a plan detailed in your hand-held notes, recording that it has been confirmed that you can breastfeed on the medication and that you understand the need to seek urgent medical support if your baby stops passing urine and doesn’t not produce appropriate colour poo (meconium, which are dark, green tar-like bowel motions, turning to yellow poo by day 5).

Fluoxetine is one of the safest of the antidepressants used in pregnancy and although ideally, it would be best to switch to a drug with a shorter half-life during the first six weeks after birth this is often not possible. Where the mother’s symptoms are well controlled it would be unfortunate to destabilise her at the most vulnerable period. In the first week after delivery, the baby may be very sleepy. Some babies, however, behave perfectly normally and there is no way of determining how a baby will react. Neonatal withdrawal and toxicity have been reported in pre-term infants, but are believed to be due to in-utero exposure to the drugs rather than withdrawal from the smaller drug levels in breastmilk.

Babies exposed to paroxetine in utero have demonstrated symptoms of neonatal withdrawal syndrome (Hudak, 2012). Symptoms may include crying, irritability, poor suck or feeding difficulties, tremor, hypoglycaemia (low blood sugar) and very rarely seizures. As with fluoxetine, hand expression may help if the baby has hypoglycaemia and poor suck initially.

Venlafaxine is a serotonin and noradrenaline reuptake inhibitor used for severe depression that hasn’t responded to other drugs. Infants exposed in utero may have adverse effects immediately at birth, including respiratory distress, difficulty breathing, seizures and temperature instability. It is not known if these are due to a direct toxic effect of venlafaxine on the foetus, or to a discontinuation (withdrawal) syndrome. Studies (Koren, 2006) have shown that adverse effects may be partially relieved by the venlafaxine received through breastmilk. Infants receive venlafaxine and its active metabolite in breastmilk, and the metabolite of the drug can be found in the plasma of most breastfed infants, but no proven drug-related side-effects have been reported (LactMed).

Beta-blockers

Babies exposed to beta-blockers in pregnancy and during the post-natal period experience different effects. These drugs are usually prescribed to mothers who have developed symptoms of pre–eclampsia, including high blood pressure. The impact of this condition means that babies are often born ‘small for dates’, or suffering from intra-uterine growth retardation (IUGR). Labour may be induced before the due date so that maternal symptoms can be halted before there is serious damage or symptoms of eclampsia develop, which can be fatal for mother and baby. In all circumstances, babies are born vulnerable. Beta-blockers are also known to affect blood glucose levels. So we have a small baby who hasn’t been well nourished due to restricted blood supply via the placenta, already at risk of low blood sugars. Drugs like labetolol and propranolol get into milk at very low levels, so are unlikely to further impact on blood sugars in the baby. However, in most units, any baby being breastfed by a mother on beta-blockers is subject to a hypoglycaemia policy, which may mean frequent heel-pricks to check blood sugars. Frequent, effective breastfeeding to stimulate a good milk supply in the mother is hugely important. Even a small volume of colostrum can boost blood sugars considerably and remove the need for formula supplements.

Extracts taken from “Why Mothers Medication Matters” Jones W Pinter and Martin 2017

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