Background: Nonsteroid anti-inflammatory drugs may cause idiosyncrasy in some susceptible individuals. This case is presented in order to make an impact on a rare form of dipyrone-associated idiosyncrasy.Case Report: A 68-year-old female was hospitalized with dyspnea, pretibial edema and fatigue. Initial complete blood count, hepatic and renal functions were normal. On 4th day of her hospitalization, she was given 500 mg dipyrone because she suffered toothache. In the following days, moderate decrement of the blood cells (WBC: 2.0i103/KL, RBC: 3.00i106/KL, Hb: 9.2 g/dl, Htc: 28%, Platelets: 82i103/KL) and further abnormality of renal function (BUN: 124 mg/dl, creatinine: 7.0 mg/dl) were encountered. On 9th day, renal functions were normal (BUN: 35 mg/dl, creatinine: 0.9 mg/dl). At that time, complete blood count values were as follows: Hb: 9.8 g/dl, Htc: 30.3%, WBC: 5.1i103/KL, Platelets: 237i103/KL. Conclusions: Dipyrone-associated idiosyncrasy may result serious abnormalities in renal and hemopoetic functions. Therefore, using dipyrone must require attention in certain situations.

Keywords: bone marrow suppression, Dipyrone, Idiosyncrasy