There are different factors influencing the treatment of depression. An important factor is co-morbidity. We made an analysis of depression treatment within general practice in Estonia as part of the PREDICT study in 2003-2005. The study group consisted of consecutive patients (n=1094), aged 18-75 years, who sought consultation from their family doctor. We found that more antidepressants, anxiolytics, and hypnotics were prescribed to patients with co-morbid mental disorder (odds ratio [95% confidence interval] 5.49 [3.61-8.40], 8.38 [5.33-13.18], and 4.02 [2.30-7.02], respectively) compared to those patients who did not have this disorder.