Effect of Curcumin on Sulfasalazine Pharmacokinetics in Healthy Volunteers

Abstract

Curcumin, a commonly used spice, is a naturally occurring polyphenol. It has been reported that curcumin inhibited the transport activity of breast cancer resistance protein (BCRP/ABCG2) in animal studies, and curcumin caused significantly increased plasma concentrations of sulfasalazine (SASP), an in vivo probe for BCRP function in human. In this study, we assessed the influence of prior administration of curcumin on the pharmacokinetics of SASP. An open-label, single-arm and two-phase study was conducted in 34 healthy participants. A single dose of SASP (2,000 mg) was administered orally after overnight fast (phase 1). After seven days washout period, a single oral dose of curcumin (2,000 mg) was administered, and then, 4 days to 5 days after administration of curcumin, 2,000 mg of SASP was administered orally again (phase 2). Plasma concentrations of SASP were assayed by highperformance liquid chromatography. Orally 4 days to 5 days’ time lag between SASP and curcumin intake disappeared the interaction. The disappeared interaction may be responsible for the extremely low bioavailability of curcumin and the disappearance of curcumin in the gastro-intestinal tracts before the administration of SASP. Our findings suggested that 4 days to 5 days’ time lag is necessary to avoid the drug interaction between BCRP substrates and curcumin.