Public knowledge and factors associated with inappropriate analgesic use: a survey in Thailand.

Objective: This study aims to evaluate knowledge of analgesics and factors associated with inappropriate analgesic use among the public.

Methods: The cross-sectional study was carried out in one large city in the south of Thailand. The survey was conducted using interview of people of age 16 or older. The questionnaire elicited information regarding knowledge, attitudes and behaviours on analgesic use including prevalence of taking paracetamol >4 g/day (overdosage) and not taking non-steroidal anti-inflammatory drugs (NSAIDs) with meals (inappropriate taking).

Key Findings: Of 1982 participants, paracetamol overdose (n = 595) and inappropriate NSAID users (n = 751) were less likely to give correct answers about analgesics compared with appropriate users. The overdose use was inversely associated with knowledge on paracetamol (odds ratio (OR) 0.90; 95% confidence interval (CI), 0.83, 0.98) but directly associated with positive attitudes towards high dose taking (OR 2.15; 95% CI, 1.49, 3.11), and high frequency of analgesic use (OR 1.78; 95% CI, 1.24, 2.54). Inappropriate NSAID ingestion was inversely associated with knowledge on NSAIDs and directly associated with more commonly obtaining analgesics from community pharmacies (OR 0.87; 95% CI, 0.82, 0.92 and OR 1.27; 95% CI, 1.01, 1.61, respectively).

Conclusions: Poor knowledge, positive attitudes towards high dose or high frequency of analgesic consumption and the patterns of using drugs were associated with inappropriate analgesic use especially that of paracetamol.