Reading the article: ‘Metamizole for postoperative pain therapy in 1177 children’1 recently published in the European Journal of Anaesthesiology provoked us to reflect on our daily prescription of metamizole in Brazil.
Dipirona (metamizole) is certainly by far the most used analgesic and antipyretic in Brazil; orally or by intravenous injection, and we do not observe as much adverse drug reaction as suggested by the literature. In only a single hospital (Santa Casa de Belo Horizonte), 5257 ampoules of 1000 mg of Dipirona were administered for 3793 surgical patients over 3 months (October to December 2015 – Internal Data of Hospital Santa Casa de Belo Horizonte – Departamento de Anestesiologia). For postoperative pain therapy, in the absence of known allergy or adverse reactions, we usually give high doses such as 2000 mg intravenously to adult patients at the end of surgery, and 30 to 50 mg kg−1 to children, before the end of surgery. Apart from being an excellent analgesic, its cost is very low, making it even more attractive.
Despite its widespread use for the treatment of pain and fever in Brazilian patients, the Brazilian literature does not provide any articles about the incidence or the severity of its adverse effects.
So trying to answer the question from Rollason and Desmeules2 in the accompanying Invited Commentary ‘Is the benefit worth the risk?’, we believe the answer is ‘yes’. Metamizole (Dipirona) is probably well tolerated and we should try to find out if there is any genetic predisposition of a specific population for the development of agranulocitosis.
In conclusion, based on our widespread use of Dipirona (metamizole), with few adverse drug reactions, in Brazil, to reduce opioid use metamizole can be used as a first-line therapy for postoperative pain in surgical patients.
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1. Fieler M, Eich C, Becke K, et al. Metamizole for postoperative pain therapy in 1177 children. A prospective, multicentre, observational, postauthorisation safety study. Eur J Anaesthesiol
2. Rollason V, Desmoulles J. Use of metamizole in children and the risk of agranulocytosis. Is the benefit worth the risk? Eur J Anaesthesiol