BACKGROUND Although Thailand has relied on the use of compulsory drug detention centres as a strategy to try to address problematic drug use, little is known about the effects of exposure to these centres on people who inject drugs (IDU). Therefore, we undertook this study to explore whether exposure to compulsory drug detention was associated with avoiding healthcare among Thai IDU. METHODS Using Poisson regression analyses, we examined the relationship between compulsory drug detention exposure and avoiding healthcare among participants in the Mitsampan Community Research Project based in Bangkok. RESULTS 435 IDU participated in this study, including 111 (25.5%) participants who reported avoiding healthcare. In multivariate analyses, avoiding healthcare was positively associated with exposure to compulsory drug detention (adjusted prevalence ratio [APR]=1.60; 95% confidence interval [CI]: 1.16-2.21), having been refused healthcare (APR=3.46; 95% CI: 2.61-4.60), and experiencing shame associated with one's drug use (APR=1.93; 95% CI: 1.21-3.09). CONCLUSION Exposure to compulsory drug detention was associated with avoiding healthcare among Thai IDU, suggesting that this system of detention may be contributing to the burden of preventable morbidity among IDU in this setting. Although further research is needed to confirm these findings, the results of this study reinforce previous calls to replace the system of compulsory drug detention with evidence-based public health interventions for IDU.