Rifampicin and vitamin D metabolism.
A 2-wk course of rifampicin orally (600 mg/day) in 8 male subjects resulted in a consistent fall in plasma 25-hydroxycholecalciferol (25-OHD) levels of around 70%, accompanied by increased oxidation of antipyrine and 6 beta-hydroxycortisol (indicative of hepatic enzyme induction). Plasma levels of 1,25-dihydroxycholecalciferol, parathyroid hormone, and calcitonin were not altered. The fall in 25-OHD may represent the earliest lesion of drug-induced osteomalacia.
D000328:Adult; D002118:Calcium / Q000378:metabolism; D004790:Enzyme Induction; D006801:Humans; D006887:Hydroxycholecalciferols / Q000097:blood; D008297:Male; D006899:Mixed Function Oxygenases / Q000096:biosynthesis; D010018:Osteomalacia / Q000139:chemically induced / Q000378:metabolism; D010281:Parathyroid Hormone / Q000097:blood; D012293:Rifampin / Q000009:adverse effects*; D013997:Time Factors; D014807:Vitamin D / Q000378:metabolism*
D006887:Hydroxycholecalciferols; D010281:Parathyroid Hormone; D014807:Vitamin D; D006899:Mixed Function Oxygenases; D002118:Calcium; D012293:Rifampin