Are there data on how often thyroid hormone augmentation is effective?
Studies examining augmentation of TCAs and selective serotonin reuptake inhibitors (SSRIs) reveal that patient response rate is approximately 50%. However, there is a wide variation in reported response rates across these studies (25% to 90%). In general, researchers report that clinicians can expect £50% of patients to respond with this strategy. In addition, a meta-analysis showed that patients taking triiodothyronine (T)3 were twice as likely to respond to antidepressant treatment versus placebo, which would be consistent with a 50% response rate.1 This response rate is similar to the rate of lithium, which is also £50%. These findings raise the important question of why clinicians believe thyroid hormone augmentation is non-efficacious. Although data are limited, research shows that this augmentation does work, although studies determining which patients most benefit from this treatment should be conducted. Currently, of the 14–15 studies evaluating thyroid augmentation with TCAs a
