It can take several weeks for an antidepressant to take effect. After several weeks of treatment, fewer than 50% of patients are in remission, in other words showing no or only minor symptoms of depression. After checking that the disorder is not due to an underlying illness or an ongoing treatment, for example, and that the patient followed the antidepressant treatment correctly for at least 6 weeks, a change of treatment may be necessary if there is no sign of remission.
The doses of antidepressant can be increased to the maximum recommended amount if the drug’s adverse effects do not cause the patient too much discomfort. In some cases, the antidepressant can be changed, after a break to avoid the risk of the drug interaction. The combination of two antidepressants mainly exacerbates the adverse effects and brings no tangible clinical benefits. The addition of other drug treatments has not been widely evaluated and can potentially lead to serious adverse effects. The addition of a neuroleptic is sometimes effective, but it increases the risk of adverse effects.
Combination with psychotherapy, especially cognitive behavioural and interpersonal therapy, is more effective in reducing the symptoms of depression, but must take account of the patient’s wishes.
In the event of a severe depressive episode, electroconvulsive therapy is an option if other treatments fail or when the risk of suicide warrants rapid and effective intervention. Transcranial magnetic stimulation seems promising but the optimum method of treatment remains to be defined.
©Prescrire 1 May 2011
"Treatment-resistant depression: no panacea, many uncertainties" Prescrire Int 2011; 20 (116): 128-133. (pdf, subscribers only)