Background In Portugal, there are no published data on the health-related consequences of prescription drug misuse, which is therefore a public health issue of unknown dimension in our country. Poison control centres and other pharmacoepidemiological sources can be part of a surveillance system for monitoring medicine's use and misuse. Methods Retrospective observational study of intentional exposures to opioid analgesics, antiepileptics, antidepressants, anxiolytics, hypnotics and sedatives reported to the Portuguese Poison Information Centre (CIAV) between 2014 and 2018. Variables studied were demographic characteristics of individuals, geographic distribution of calls, co-exposure to alcohol or illicit drugs, call origin, case evaluation and guidance. Results CIAV received 24624 calls reporting 34203 intentional exposures to any medicine, 31169 (91.1%) of which involving one of the studied psychoactive medicines and 20906 exposures having emergency room advice or effective hospitalisation. The most frequently involved medicines were benzodiazepines (62.0%) - alprazolam (15.4%) and diazepam (12.0%) - with trazodone ranking fifth (6.0%). Combination with non-medicinal products was seen in 2169 calls (9.4%), 2052 (94.6%) of which with alcohol. Conclusions There is female predominance in the poisonings reported involving any of the medicines studied. Benzodiazepines and antidepressants are the top classes reported. The rate of intentional exposures to psychoactive medicines is higher in Coimbra district, whose significant university student population requires further analysis of data. To adjust for the variability in the level of medicines' use in the population, work is undergoing to include rates of intentional poisonings in patients prescribed the studied medicines. To better characterise the potential consequences of misuse of psychoactive prescription drugs in Portugal, additional data on deaths involving these medicines will also be included in the project. Key messages First published Portuguese data on prescription drug poisoning reported to CIAV. First Portuguese project to analyse prescription drug poisoning, forensic and hospitalisation data.