"Small benefits at higher doses with SSRIs but not TCAs. Both have more adverse effects at higher doses."
A 2015 systematic review of SSRI dose-response relationships included 40 studies involving 10,039 participants.1 The slightly increased benefits of SSRIs at higher doses are somewhat offset by decreased tolerability at high doses. The maximum doses plateaued at 50 mg/day of fluoxetine equivalent. The benefit was not quantified.
In a 2009 Cochrane review low dose tricyclic antidepressants (TCAs), 75 to 100 mg per day were as effective as higher doses.2 However the higher doses have more adverse effects.
Most of the effects from antidepressants in primary care are from the placebo effect which is about 50%. For mild and moderate depression there is 6% and 9% additional benefit from prescribing antidepressants.3
Gems are chosen by the Goodfellow director Dr. Bruce Arroll to be either practice changing or practice maintaining. The information is educational and not clinical advice.