Toxicity of co-trimoxazole in nutritional haematinic deficiency

A woman of 47 habituated to analgesics and living on an inadequate diet was deficient in iron, folate and vitamin B(12). Treatment of pyelonephritis with co-trimoxazole precipitated pancytopenia with a megaloblastic bone marrow. She recovered following withdrawal of the drug and administration of iron, folate and vitamin B(12).