Adverse effects of antidepressants are most common at the beginning of the treatment, but possible also later. We examined the association between antidepressant use and work-related injuries taking into account the duration of antidepressant use.

Antidepressant use and work-related injuries between 2000 and 2011 were measured among 66 238 employees (mean age 43.8 years, 80% female) using linkage to national records (the Finnish Public Sector study). We analysed data using time-dependent modelling with individuals as their own controls (self-controlled case-series design).

In 2238 individuals who had used antidepressants and had a work-related injury during a mean follow-up of 7.8 years, no increase in the risk of injury was observed in the beginning of antidepressant treatment. However, an increased injury risk was seen after 3 months of treatment (rate ratio, compared with no recent antidepressant use, 1.27, 95% confidence interval 1.10–1.48). This was also the case among those who had used only selective serotonin reuptake inhibitors (n = 714; rate ratio 1.41, 95% confidence interval 1.08–1.83).

Antidepressant use was not associated with an increased risk of work-related injury at the beginning of treatment. Post-hoc analyses of antidepressant trials are needed to determine whether long-term use of antidepressants increases the risk of work-related injury.