Electrolyte/Urinary Alkalinizer
PREGNANCY RECOMMENDATION: Limited Human Data—Probably Compatible
BREASTFEEDING RECOMMENDATION: No Human Data—Probably Compatible
PREGNANCY SUMMARY
Except for the case discussed below, no other reports describing the use of potassium citrate in human pregnancy have been located. In four animal species, no teratogenicity was observed with very high doses of citric acid. Citric acid is widely distributed in nature and is a key ingredient in intermediary metabolism. In addition, potassium is a natural constituent of human tissues and fluids. The primary risk appears to be from hyperkalemia, as this product could produce this in patients who have a condition predisposing them to high blood potassium levels. Because high levels are detrimental to maternal and embryo–fetal cardiac function, maternal serum potassium levels should be closely monitored.
FETAL RISK SUMMARY
Potassium citrate, the potassium salt of citric acid, is given orally to raise the urinary pH. Citric acid is the acid of citrus fruits and is widely distributed in nature. After absorption, metabolism of citrate increases the alkaline load. Potassium citrate is indicated for the management of renal tubular acidosis with calcium stones, hypocitraturic calcium oxalate nephrolithiasis of any etiology, and uric acid lithiasis with or without calcium stones (1).
Reproduction studies have been conducted with citric acid in mice, rats, rabbits, and hamsters. The highest doses studied were 241, 295, 425, and 272 mg/kg, respectively. No teratogenicity was observed in these species (2).
A 1964 report mentioned the use of potassium citrate in one pregnant patient (3). The liveborn infant had an unspecified malformation, but no other details, such as the timing of the exposure, dose, other drugs used, and the medical and obstetric history, were provided.
BREASTFEEDING SUMMARY
No reports describing the use of potassium citrate during lactation have been located. Breast milk is naturally high in potassium with levels that are 3–4 times those in plasma (4). The concentration of potassium in mature milk is about 55–57 mg/dL (about 14–15 mEq/L) (4). Because potassium freely passes into and out of milk, the use of potassium citrate by a lactating woman with normal plasma potassium levels would have no adverse effect on a nursing infant. However, if the woman has hyperkalemia, this could result in higher milk potassium concentrations. In this case, nursing infants should be observed for gastrointestinal complaints commonly observed in adults with oral potassium and plasma potassium concentrations should be monitored.
References
1.Product information. Potassium Citrate. Upsher-Smith Laboratories, 2006.
2.Anonymous. Food and Drug Research Labs, Inc.: Teratologic evaluation of FDA 71–54 (citric acid). NTIS Report PB-223 814, 1973. As cited in Shepard TH. Catalog of Teratogenic Agents. 10th ed. Baltimore, MD: The Johns Hopkins University Press, 2001:115.
3.Mellin GW. Drugs in the first trimester of pregnancy and the fetal life of Homo sapiens. Am J Obstet Gynecol 1964;90:1169–80.
4.Lawrence RA, Lawrence RM. Biochemistry of human milk. In Breastfeeding. A Guide for the Medical Profession. 5th ed. St. Louis, MO: Mosby, 1999:127.