To      : Denise
Re      : Methyldopa

Methyldopa is known to suppress the blood pressure of newborn infants for at
least 2 days postpartum when prior to delivery.  This could be a cause for some
sedation, or weakness.

The amount transferred into milk is quite minimal, or less than 1.14 mg/liter
of milk following a dose of 1000 mg/day.  Its poorly absorbed orally (25-50%),
so the neonatal exposure via milk is quite minimal.

Sedation is know to occur in new users of methyldopa, but generally wanes after
a few days of therapy.  If this infants blood pressure is in the normal range,
its probably just a sleepy neonate and not drug related.

Regards

Tom Hale




I have an enquiry from concerned parents about the effects of maternal
methyldopa on their breastfeeding baby.  The baby is settled and is
gaining weight.  It is being demand fed to a four hourly limit (hospital
policy because of birth weight under 2.8 kgs) and needs to be woken for
most feeds although feeds well once woken.  Dad feels the baby is
excessively sleepy and was wondering whether the Methyldopa could cause
this.  Does anyone know if this is known to occur ?  Perhaps Dr. Hale
might have some information on this one.  I would appreciate being
emailed directly as I am NOMAIL at the moment because of time
constraints.

Thanks,  Denise Hartley  RN RM IBCLC (Queensland, Australia)