Summary of Use during Lactation

Hydrochlorothiazide doses of 50 mg daily or less are acceptable during lactation. Intense diuresis with large doses may decrease breastmilk production.

Drug Levels

Maternal Levels. In a mother who was 28 days postpartum, hydrochlorothiazide reached a peak milk level of about 275 mcg/L at about 3 hours after a 50 mg oral dose. The infant received a daily dosage of about 2% of the mother's weight-adjusted dose.[1]

Infant Levels. Hydrochlorothiazide was not detectable (<20 mcg/L) in the serum of a 28-day-old breastfed infant at about 2 and 11 hours after the mother's dose.[1]

Effects in Breastfed Infants

No electrolyte abnormalities were noted in one 28-day-old infant who was breastfed since birth while his mother was taking oral hydrochlorothiazide 50 mg daily.[1]

Effects on Lactation and Breastmilk

Hydrochlorothiazide in dosages of 100 mg daily in the morning and 50 mg in the afternoon or 50 mg twice daily have been used to successfully to suppress lactation at various times postpartum.[2,3] Intense diuresis with thiazides and thiazide-like diuretics, fluid restriction and breast binding have been used to suppress postpartum lactation.[2,4,5] The added contribution of the diuretic to these measures, which are effective in suppressing lactation, has not been studied. There are no data on the effects of diuretics on established, ongoing lactation.

Alternate Drugs to Consider

Chlorothiazide

References

1.

Miller ME, Cohn RD, Burghart PH. Hydrochlorothiazide disposition in a mother and her breast-fed infant. J Pediatr 1982;101:789-91. [PubMed: 7131161]

2.

Stout G. Suppression of lactation. Br Med J 1962;1:1150.

3.

Reisfield DR, Paret FL. Value of a diuretic in suppressing breast engorgement. J Med Soc N J 1966;63:458-61. [PubMed: 5341754]

4.

Healy M. Suppressing lactation with oral diuretics. Lancet 1961;277(7190):1353-4. doi: 10.1016/S0140-6736(61)90289-6 [CrossRef]

5.

Reiher KH. Suppression of lactation by stimulation of diuresis. Zentralbl Gynakol 1963;85:188-90. [PubMed: 13973786]

Substance Name

Hydrochlorothiazide

CAS Registry Number

58-93-5

Drug Class

Breast Feeding

Lactation

Milk, Human

Antihypertensive Agents

Thiazide Diuretics