Tetracycline-induced aplastic anemia.

A 54-year-old man developed mild renal insufficiency after treatment with gentamicin and cephalothin. He then received tetracycline for eight days, 500 mg orally four times daily, for a total dose of 15 gm. Twelve days after discontinuation of the drug, a severe but reversible aplastic anemia developed. We propose that bone-marrow-toxic concentrations of tetracycline resulted from the preexisting renal insufficiency. Because of the temporal relationship between tetracycline administration and aplastic anemia, and the lack of any other explanation, we conclude that this case illustrates a rare but potentially fatal complication of this drug.