ASK DIS: Breastfeeding: AntiHypertensive Medications

Postpartum hypertension may be due to persistence of antepartum or intrapartum hypertension, or may be of new onset.
been observed in as many as 20 percent of women within six weeks of delivery
Preeclampsia-related hypertension usually resolves spontaneously within a few weeks (average 16±9.5 days) and is almost always gone by 12 weeks postpartum
Blood pressure may be significantly higher in the immediate postpartum period than antepartum or intrapartum.
due to a combination of factors, including administration of intravenous fluids to women who have had a cesarean delivery or neuraxial anesthesia for labor, loss of pregnancy associated vasodilation after delivery, mobilization of extravascular fluid after delivery, and administration of non-steroidal antiinflammatory agents for postdelivery analgesia
New onset postpartum hypertension may be due to a combination of factors, including administration of a large volume of saline solution to women who have had a cesarean delivery or neuraxial anesthesia for labor, loss of pregnancy associated vasodilation after delivery, mobilization of extravascular fluid after delivery, administration of non-steroidal antiinflammatory agents for postdelivery analgesia, and subclinical preeclampsia

Management

Oral medications similar to those used in the nonpregnant population are prescribed, with modifications if the woman is breastfeeding

Diuretics

Brief furosemide therapy (20 mg orally once or twice per day for five days) may facilitate return to normotension in women with severe hypertension, especially if accompanied by debilitating edema; however, the use of diuretics in this setting has not been studied extensively
Theoretically, diuretics may reduce milk volume, but the AAP considers their use compatible with breastfeeding

Beta-blockers and alpha/beta-blockers

Propranolol, metoprolol, and labetalol have the lowest transfer into milk, with relative infant doses of less than 2 percent. None has been associated with adverse events in infants.
In contrast, atenolol and acebutolol are relatively extensively excreted into breast milk and beta-blockade in nursing infants has been reported, therefore, other agents are preferable for women who are nursing an infant less than 3 months of age or a preterm infant, or who are taking a high maternal dose.
Because there is little to no published experience with carvedilol or bisoprolol during breastfeeding, other agents may be preferred, especially while nursing a newborn or preterm infant.

Calcium channel blocker

Diltiazem, nifedipine, nicardipine, and verapamil are associated with a relative infant dose of less than 2 percent.
The American Academy of Pediatrics (AAP) lists all three as compatible with breastfeeding

Angiotensin converting enzyme (ACE) inhibitors –

are transferred into milk at very low levels.
Captopril and enalapril have been reviewed by the AAP and are compatible for use in lactation.
However, newborns may be more susceptible to the hemodynamic effects of these drugs, such as hypotension, and sequelae such as oliguria and seizures.
Therefore, we suggest that the hemodynamic status of the infant be taken into account when deciding whether women taking these drugs should breastfeed.
There is no information on use of angiotensin II receptor blockers during breastfeeding.

Methyldopa

MHRA newsletter identifies methyldopa as the antihypertensive of choice during breastfeeding.
However, the MHRA Drug Safety Update does not reflect the association between methyldopa and clinical depression, and the GDG’s view is that methyldopa should not be used in the postnatal period because women are already at risk of depression at this time

Recommendations

In women who still need antihypertensive treatment in the postnatal period, avoid diuretic treatment for hypertension if the woman is breastfeeding or expressing milk.

Tell women who still need antihypertensive treatment in the postnatal period that the following antihypertensive drugs have no known adverse effects on babies receiving breast milk:

Tell women who still need antihypertensive treatment in the postnatal period that there is insufficient evidence on the safety in babies receiving breast milk of the following antihypertensive drugs:

Assess the clinical wellbeing of the baby, especially adequacy of feeding, at least daily for the first 2 days after the birth.
† This guideline assumes that prescribers will use a drug’s summary of product characteristics (SPC) to inform decisions made with individual patients. Drugs for which particular attention should be paid to the contraindications and special warnings during pregnancy and lactation are marked with †

References:

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