ACE inhibitors and angiotensin II receptor blockers should be avoided in pregnancy and during breastfeeding

The UK’s Medicines and Healthcare products Regulatory Agency recommended that ACE inhibitors and angiotensin II receptor antagonists should not be used by breastfeeding mothers in the first few weeks after delivery, because of possible profound neonatal
hypotension.

ACE inhibitors and angiotensin receptor blockers recommendations when breastfeeding

These are the recommendations straight from the May 2009 Drug Safety Update (pdf):

Captopril, enalapril, or quinapril: use in breastfeeding is not recommended in the first few after delivery because of the possibility of profound neonatal
hypotension; preterm babies may be at particular risk.

Use may be considered when the infant is older if an ACE inhibitor is necessary for the mother; careful
follow-up of the infant for possible signs of hypotension is recommended

Ramipril, lisinopril, fosinopril, trandolapril, moexipril, or perindopril: use in breastfeeding is not recommended. Alternative treatments with more established safety profiles during breastfeeding are preferable, especially while nursing a newborn or preterm baby.

All angiotensin II receptor antagonists:
Use in breastfeeding mothers is not recommended. Alternative antihypertensive treatments with more established safety profiles during breastfeeding are
preferable, especially while nursing a newborn or preterm baby.

ACE inhibitors and angiotensin II receptor blockers in pregnancy

The following is an excerpt on ACE inhibitors in pregnancy, taken from: “Update on the Use of Antihypertensive Drugs in Pregnancy”. Tiina Podymow and Phyllis August. Hypertension. 2008

Angiotensin-converting enzyme inhibitors (ACE-I) and angiotensin receptor blocking agents are contraindicated in the second or third trimesters because of toxicity associated with reduced perfusion of the fetal kidneys; use is associated with a fetopathy similar to that observed in Potter’s syndrome (ie,
bilateral renal agenesis), including renal dysgenesis, oligohydramnios as a result of fetal oliguria, calvarial and pulmonary hypoplasia, intrauterine growth restriction, and neonatal anuric renal failure, leading to death of the fetus.
Angiotensin receptor blocker use in pregnancy has also caused fetal demise, attributed primarily to renal failure.

First-trimester exposure to ACE-I has been associated
recently with a greater incidence of malformations of the cardiovascular and central nervous systems.

Whether adverse outcomes are because of a hemodynamic effect in the fetus or specific (nonhemodynamic) requirements for angiotensin II as a fetal growth factor is unknown. As such, first-trimester use of ACE-I and angiotensin receptor blocking agent medications should be avoided.

Bottom line

ACE inhibitors and angiotensin receptor blockers  should be avoided  in the from first to third trimesters of pregnancy and while breastfeeding.