Excretion of drugs in human milk

Abstract

Nursing infants may potentially be affected by any drug ingested by the mother; this report provides a tabulated listing of drugs present or absent in human milk and attempts to evaluate their significance to the nursing infant. Certain enzyme systems which detoxify drugs in the adult are not present in the neonate. Chloramphenicol and sulfisozazole are examples of such enzyme-dependent systems and may cause kernicterius and Gray syndrome. Psychological and physiological factors can affect the composition of the milk and alter the transfer of various drugs into the milk. Passive diffusion is the main mechanism of transfer of drugs from plasma to milk, but other important means include lipid solubility, route of drug administration drug dissociation constants, protein binding phenomena and active transport. A table lists drugs, their excretion and significance for nursing in the following categories: 1) antihistamine drugs, 2) antiinfective agents, 3) antineoplastics, 4) autonomic drugs, 5) blood formation and coagulation, 6) cardiovascular drugs, 7) central nervous system drugs, 8) diagnostic agents, 9) electrolytic caloric and water balance, 10) expectorants and cough preparations, 11) gastrointestinal drugs, 12) hormones and synthetic substitutes, 13) radioactive agents, 14)serums, toxoids, and vaccines, 15) skin and mucous membrane preparations, and 16) vitamins.