Probenecid has been available for more than 50 years. It is a uricosuric and renal tubular transport–blocking agent. The drug crosses the human placenta, at least at term. The only reports of its use as a uricosuric in human pregnancy involved women with preeclampsia, not gout. In addition, reports have described its use to partially block the urinary excretion of antibiotics in pregnancy. The combined data do not suggest a risk of structural defects or other forms of developmental toxicity. Animal reproduction studies have apparently not been conducted.
Allopurinol, colchicine, and probenecid are excreted into breast milk and are – or probably are – compatible with breastfeeding. Febuxostat is probably excreted, but there is potential toxicity and nursing infants who may be exposed to the drug in milk should be monitored for liver function abnormalities, nausea, arthralgia, and rash. It is unlikely that pegloticase will be excreted into milk because of its very high molecular weight. However, even if it were excreted, the drug most likely would be digested in the infant’s gut.
Mr. Briggs is a pharmacist clinical specialist at the outpatient clinics of Memorial Care Center for Women at Miller Children’s Hospital in Long Beach, Calif.; a clinical professor of pharmacy at the University of California, San Francisco; and an adjunct professor of pharmacy at the University of Southern California, Los Angeles, and Washington State University, Spokane. He also is a fellow of the American College of Clinical Pharmacy, coauthor of "Drugs in Pregnancy and Lactation," and coeditor of "Diseases, Complications, and Drug Therapy in Obstetrics." He said he had no disclosures related to the topic of this article.
* Correction, 3/2/12: An earlier version of this story reported the incorrect year of publication of a British study describing 158 subjects with a dominantly inherited disorder known as familial juvenile hyperuricemic nephropathy.