Эффективность использования высоких доз антидепрессантов

Higher doses than those currently used might be modestly more effective, but come with higher risks of adverse effects.

Before writing medications off as ineffective or only partially effective, clinicians strive to optimize dosing. To better identify optimal doses for six selective serotonin reuptake inhibitors (SSRIs), investigators applied meta-analytic techniques to 40 studies involving 10,039 patients with major depression in placebo-controlled randomized trials who were treated with fluoxetine, (N=2386), fluvoxamine (N=910), paroxetine (N=3424), sertraline (N=865), citalopram (N=1349), or escitalopram (N=1105).

Focusing on efficacy and tolerability, investigators calculated number needed to treat (NNT) and number needed to harm (NNH). They used published dose ranges to convert SSRI doses to imipramine equivalents, with 100 mg of imipramine equivalent to:

Sertraline, 120 mg

Fluvoxamine, 100 mg

Paroxetine, 20 mg

Fluoxetine, 20 mg

Citalopram, 33.3 mg

Escitalopram, 16.7 mg

Statistical modelling adjusted for lag times of medication-effect onsets and for doses used in the trials (100–400 mg of imipramine equivalents). In dose-by-time interaction analyses, higher doses yielded greater therapeutic responses. Greatest efficacy was seen for 200–250-mg imipramine equivalents, compared with higher and lower ranges (NNTs: compared with placebo, 3; in lower-dose comparisons, 14–16). Compared with low doses, higher dose was associated with greater likelihood of dropout due to adverse effects (NNHs, 45–48), but all-cause dropouts were fewer at higher doses, presumably due to efficacy. Fluvoxamine, approved for depression in other countries but not by the FDA, was excluded in some analyses, which yielded similar overall results.

Comment

These findings generally support the use of higher dose ranges for several SSRIs for major depression that did not respond or only partially responded to SSRIs. Most clinicians treating obsessive-compulsive disorder and bulimia nervosa are already comfortably using these higher doses. However, distinctions among SSRIs are warranted; for example, the FDA has issued warnings about QTc interval prolongation with higher doses of citalopram.

 Optimal Doses for SSRIs in Treating Depression: Meta-Analytic Results