Studies carried out in the 1970s and 1980s showed that there were country-dependent disparities in the information given for the same drug in medical advertisements. National and international regulations have been published to do away with such disparities and to foster the rational use of drugs. The purpose of this study was to compare the information contained in psychoactive drug advertisements published in psychiatric journals in Brazil, the United States and the United Kingdom, before and subsequent to the publication of the United States Export Act, in 1986, the WHO criteria, in 1988, and the Brazilian Sanitary Surveillance Agency Resolution no. 102, in 2000. TYPE OF STUDY AND SETTING: Content analysis, at Centro Brasileiro de Informações sobre Drogas Psicotrópicas (Cebrid).