Captopril in human blood and breast milk

Area of Science:

• Pharmacology
• Lactation Studies
• Cardiovascular Therapeutics

Background:

• Captopril is a widely used antihypertensive medication.
• Understanding drug transfer into breast milk is crucial for nursing mothers.
• Limited data exists on captopril's passage into human milk.

Purpose of the Study:

• To quantify captopril concentrations in the blood and breast milk of lactating women.
• To determine the extent of captopril transfer from maternal blood to breast milk.
• To assess the potential for selective restriction of captopril by the human mammary gland.

Main Methods:

• 12 lactating normotensive women received 100 mg captopril orally three times daily for seven doses.
• Blood and breast milk samples were collected to measure captopril concentrations.
• Pharmacokinetic parameters, including peak concentrations and time to peak, were analyzed.

Main Results:

• Average peak blood captopril concentration was 713.1 ng/ml.
• Average peak breast milk captopril concentration was significantly lower at 4.7 ng/ml.
• Time to peak concentration was faster in blood (1.1 hours) than in milk (3.8 hours).

Conclusions:

• The human breast appears to selectively restrict the passage of captopril from blood into milk.
• The low milk-to-blood ratio suggests minimal exposure for breastfeeding infants.
• Further studies may be warranted to confirm safety for breastfeeding mothers on captopril therapy.