Dipyrone and agranulocytosis: what is the risk?

• Published in: The Lancet (British edition) 2002-11, Vol.360 (9344), p.1438-1438
• Main Authors: Edwards, Jayne E, McQuay, Henry J
• Format: Article
• Language: English
• Subjects: Agranulocytosis - chemically induced; Analgesics; Anti-Inflammatory Agents, Non-Steroidal - adverse effects; Dipyrone; Dipyrone - adverse effects; Disease; Health risk assessment; Humans; Neutropenia; Prescriptions; Risk; Side effects
• ISSN: 0140-6736; 1474-547X
• DOI: 10.1016/S0140-6736(02)11489-9

Despite rigour in Hedenmalm and Spigset's definition of agranulocytosis, collection of data, and attribution, the Swedish data are based on a small number of events. If these were reflected in populations in which dipyrone is commonly used, as in Spain or Brazil, many individuals would succumb to agranulocytosis every year. Yet the literature and clinical experience do not readily support this. Under-reporting is one explanation for low reported event-rates in countries with high use of dipyrone, but would not alone account for the short-fall if the Swedish rates are to be applied. Increased susceptibility in naive populations is another possibility discussed by Hedenmalm and Spigset, but several of the cases had used dipyrone before. The widely criticised2,3 International Agranulocytosis and Aplastic Anemia Study (hAAS)4 found vastly varying risks in different countries. Methodological issues aside, different incidences could be related to several factors. Consumption and frequency of use of dipyrone differs from country to country, and some populations may have increased genetic susceptibility to agranulocytosis.