BACKGROUND Antidepressant prescribing continues to rise. Contributing factors are increased long-term prescribing and possibly the use of higher selective serotonin re-uptake inhibitor (SSRI) doses. AIM To review general practice patients prescribed the same antidepressant long-term (≥2 years) and evaluate prescribing and management pre and post-review. DESIGN AND SETTING Prospective observational cohort study using routine data from 78 urban general practices, Scotland. METHOD All patients prescribed antidepressants (excluding amitriptyline) for ≥2 years were identified from records November 2009 to March 2010. GPs selected patients for face-to-face review of clinical condition and medication, December 2009 to September 2010. Pre- and post-review data were collected; average antidepressant doses and changes in prescribed daily doses were calculated. Onward referral to support services was recorded. RESULTS 8.6% (33 312/388 656) of all registered patients were prescribed an antidepressant, 47.1% (15 689) were defined as long-term users and 2849 (18.2%) were reviewed. 811 (28.5%) patients reviewed had a change in antidepressant therapy: 7.0% stopped, 12.8% reduced dose, 5.3% increased dose, and 3.4% changed antidepressant, resulting in 9.5% (95% CI = 9.1% to 9.8% P<0.001) reduction in prescribed daily dose and 8.1% reduction in prescribing costs. 6.3% were referred onwards, half to NHS Mental Health Services. Pre-review SSRI doses were 10-30% higher than previously reported. CONCLUSION Almost half of all people prescribed antidepressants were long-term users. Appropriate reductions in prescribing can be achieved by reviewing patients. Higher SSRI doses may be contributing to current antidepressant growth.