ObjectivesThe Drug Burden Index (DBI) tool quantifies individual exposure to anticholinergic and sedative medications. The DBI has been internationally validated against adverse health outcomes in older people. DBI exposure has not been reported in the Irish older population. This study aimed to: (1) develop a list of drugs with clinically significant anticholinergic and/or sedative effects (DBI medications) relevant to Ireland; (2) examine, using the DBI formula, the prevalence of exposure to DBI medications in Irish older people and (3) explore patient factors associated DBI exposure.DesignA cross-sectional national pharmacy claims database study.SettingCommunity setting using the General Medical Services (GMS) scheme pharmacy claims database maintained by the Health Service Executive Primary Care Reimbursement Services.ParticipantsIrish older individuals (aged ≥65 years) enrolled in the GMS scheme and dispensed at least one prescription item in 2016 (n=428 516).Main outcome measuresPrevalence of exposure to DBI medications and patient factors associated with DBI exposure.Results282 874 (66%) of the GMS population aged ≥65 years were exposed to at least one DBI medication in 2016. Prevalence of exposure to DBI medications was significantly higher in females than males (females 71.6% vs males 58.7%, adjusted OR 1.65, 95% CI 1.63 to 1.68). Prevalence of DBI exposure increased progressively with the number of chronic drugs used, rising from 42.7% of those prescribed 0–4 chronic drugs to 95.4% of those on ≥12 chronic drugs (adjusted OR 27.8, 95% CI 26.7 to 29.0). The most frequently used DBI medications were codeine/paracetamol combination products (20.1% of patients), tramadol (11.5%), zopiclone (9.5%), zolpidem (8.5%), pregabalin (7.9%) and alprazolam (7.8%).ConclusionsThe majority of older people in Ireland are exposed to medications with anticholinergic and/or sedative effects, particularly females and those with multiple comorbidities. The high use of low-dose codeine/paracetamol combination products, Z-drugs and benzodiazepines, suggests there are opportunities for deprescribing.