were identified from the UK General Practice Research Database. Prescribing patterns, annual prevalence, morbidity patterns, and time to discontinuation of ATD use were identified. Results: A total of 24 976 subjects received 93 091 prescriptions; 51 868 (55.7%), 38 429 (41.3%), and 2708 (2.9%) prescriptions were for tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), and other ATDs respectively. ATD prevalence increased 1.7-fold from 1992 to 2001. TCA prevalence decreased by 30% from 3.6 to 2.5 per 1,000; SSRI prevalence increased 10 times from 0.5 to 4.6 per 1,000. In new ATD users aged (10 years, the most common diagnosis associated with TCA use was nocturnal enuresis (75.1%); in those aged >15 years, it was depression (45.8%). Depression was also associated with SSRI use (69.0%). For new users with depression, the median treatment durations for TCAs and SSRIs were 30 and 58 days respectively. TCA users were more likely to terminate treatment than SSRI users (TCAs v fluoxetine: 1.40, 95% CI 1.32 to 1.47; non-fluoxetine SSRIs v fluoxetine: 1.01, 95% CI 0.96 to 1.07). Conclusions: SSRIs have gained popularity for the treatment of depression compared with TCAs. TCAs are still used despite their lack of efficacy in prepubertal depression and their moderate effect in adolescents. However, .50% of subjects discontinue treatment after two months, with TCA users stopping earlier than SSRI users. S elective serotonin reuptake inhibitors (SSRIs) were first introduced in the late 1980s, and they have been used increasingly in children following studies showing their effectiveness in adult psychiatric disorders 1 and trials showing the ineffectiveness of tricyclic antidepressants (TCAs) in childhood depression.2 Some randomised placebo controlled trials (RCTs) of SSRIs in the treatment of paediatric depressive disorders, anxiety, and obsessive-compulsive disorder (OCD) show efficacy. [3][4][5][6][7][8]