Blood Pressure Medications
Several drug classes can be used to treat hypertensive disease during lactation. These are separated by class and summarized below. Many classes are generally considered safe in the breastfeeding dyad and not an absolute indication to pump and dump. Many blood pressure medications have been found to potentially cause an increase or decrease in maternal serum prolactin levels and/or cases of galactorrhea. This is not an absolute indication to pump and dump and the clinical significance is unknown.
For more information about medications used in hypertensive crises in pregnancy, labor, or postpartum (pre-eclampsia, eclampsia, pulmonary edema), see the section on gestational hypertension/pre-eclampsia/eclampsia in Peripartum Medical Conditions.
Beta blockers are a large class of medications including labetalol/Normodyne, metoprolol/Lopressor/Toprol-XL, propranolol/Inderal, sotolol/Betapace, atenolol, nadolol, bisoprolol, carvedilol/Coreg.
The concentration of beta blockers in breast milk is mostly determined by their protein binding capacity. Some beta blockers have higher concentrations in breast milk (sotolol, atenolol, nadolol) so alternatives to these may be considered. Other beta blocking medications (labetalol, metoprolol, propranolol) have low levels in the breast milk and pose little risk of accumulation or negative effects in the dyad.
There may be a risk of developing cardiac arrhythmias in preterm infants of lactating individuals on a beta blocking medication. Therefore, alternative antihypertensive medications should be considered in individuals breastfeeding preterm infants.
While alternatives are preferred in lactating individuals with preterm infants and infants should be monitored for arrhythmias, there is no absolute indication to pump and dump when using beta blockers with low milk levels (labetalol, metoprolol, propranolol). Shared decision making should be used with beta blockers to discuss the relative risks of specific beta blockers to breastfeeding infants.
Calcium Channel Blockers
Dihydropyridine calcium channel blockers have more data underlying their use in lactation than non-dihydropyridine calcium channel blockers. There is no absolute indication to pump and dump although dihydropyridine calcium channel blockers are preferred due to the larger amount of available data surrounding their use in lactation.
- Dihydropyridine (nifedipine/Adalat/Procardia, nicardipine/Cardene, amlodipine/Norvasc, felodipine): Dihydropyridine calcium-channel blockers are found in low levels in the breast milk and are generally considered safe in the breastfeeding dyad. There is no absolute indication to pump and dump.
- Non-dihydropyridine (diltiazem/Cardizem, verapamil/Calan): There are limited data available for the use of non-dihydropyridine calcium-channel blockers in breastfeeding. The limited data available on non-dihydropyridine calcium channel blockers suggest low concentrations of these medications in breastmilk, and they would be unlikely to cause adverse effects in the nursing infant.
Hydralazine/Apresoline is a commonly used vasodilator that is found in low levels in the breast milk and breastfeeding infants. There is no absolute indication to pump and dump.
Diuretic medications are generally not an absolute indication to pump and dump.
- Thiazide (hydrochlorothiazide, chlorthalidone, indapamide/Lozol, metolazone/Zaroxolyn) & Loop (lasix/Furosemide, bumetanide/Bumex): High doses may pose a risk to infants so alternative antihypertensive medications should be considered if high doses of these medications are needed. Lactating individuals who experience dehydration because of intense diuresis could experience a decrease in milk production. While infants should be monitored for possible side effects with higher doses of these medications and lactating individuals should be counseled about the risk to milk production, low doses are not an absolute indication to pump and dump.
- Chlorthalidone: The long half-life of this medication in the lactating individual may lead to accumulation in the milk and subsequently the breastfed infant. An alternative medication should be considered (1).
- Metolazone: Little to nothing is known about this medication. Therefore, an alternative medication should be considered.
- Potassium-Sparing (spironolactone/Aldactone, amiloride/Midamor): There is no absolute indication to pump and dump.
Angiotensin Converting Enzyme (ACE) Inhibitors
ACE Inhibitors are a large class of medications including lisinopril/Zestril/Prinivil, enalapril/Vasotec, benazepril/Lotensin, captopril, ramipril, cilazapril perindopril, quinapril. Enalapril may pose a theoretical concern for a decrease in prolactin which could potentially decrease milk production so an alternative may be considered. There is no absolute indication to pump and dump with this class of medications.
Angiotensin II Receptor Blockers (ARBs)
ARBs include losartan/Cozaar, valsartan/Diovan, telmisartan/Micardis, irbesartan/Avapro. Little to nothing is known about this class of medications. Therefore, an alternative antihypertensive medication should be considered due to the lack of data, but there is not an absolute indication to pump and dump and shared decision making should be used with these medications.
Central Alpha-2 Receptor Agonists
- Clonidine: This medication is found to have high concentrations in breast milk with at least one infant who had significant side effects related to clonidine use by the lactating individual. For long term use, an alternative medication should be considered.
- Methyldopa: This medication is found in low levels in the breastmilk and infant so there is no absolute indication to pump and dump.
Peripheral Alpha-1 Receptor Blockers
Peripheral alpha-1 Receptor Blockers include doxazosin/Cardura, prazosin/Minipress, terazosin/Hytrin. Doxazosin is found in low levels in the breast milk and the breastfeeding infant and there is no absolute indication to pump and dump with doxazosin. For medications in this class (other than doxazosin), no data are available and an alternative antihypertensive medication should be considered.
- American Heart Association: Types of Blood Pressure Medications: https://www.heart.org/en/health-topics/high-blood-pressure/changes-you-can-make-to-manage-high-blood-pressure/types-of-blood-pressure-medications#diuretics