Is there any difference between the risk of weight gain as an adverse drug effect from different se

Fråga: Is there any difference between the risk of weight gain as an adverse drug effect from different serotonin uptake inhibitors? The physicians at the rehabilitation department usually prescribe sertraline instead of citalopram, since they have noticed more weight gain with citalopram than with sertraline.

Sammanfattning: Weight gain during antidepressant treatment might be a sign of improvement of the disease and not an adverse drug effect. There seems to be some differences among SSRIs in the ability to give rise to weight gain. Fluoxetine is the substance that seems to give the least weight gain and paroxetine seems to cause the highest weight gain. There is no evidence that sertraline causes less weight gain than citalopram.

Svar: Weight loss and loss of appetite are common findings in depressed patients. Weight gain during treatment might be a sign of recovery from depression. Therefore, it is difficult to determine whether or not the weight gain seen during treatment with antidepressive agents is an adverse drug reaction or a sign of increasing health. However, there are studies performed, that suggest differences among the SSRIs with respect to weight gain (1).

When sertraline and citalopram were compared, no significant difference in weight change were seen during 6 months (2). In another study, 4.5% of citalopram treated patients gained weight and 2.5% of sertraline treated patients (3). Citalopram did not increase weight compared to placebo in a 6-months study and in a 12 month long study. Five percent of 514 patients increased their weight more than 5 kg when citalopram was used (1). When citalopram and paroxetine was compared, weight gain was oberved in 37% of citalopram patients and 40% of paroxetine patients (4). When citalopram and fluoxetine was compared during 8 weeks of treatment, weight decrease was higher in the fluoxetine group than in the citalopram group (5).

When paroxetine was compared with sertaline and fluoxetine in a 32-week study, a small mean decrease in weigth was seen with fluoxetine, a small increase in mean weigth with sertraline and a significant increase with paroxetine. A significantly higher percentage of paroxetine treated patients had a weight increase of 7 kg or more, compared with fluoxetine and sertraline treated patients (6). Also, paroxetine gave a significantly higher weight gain, compared to sertraline, in a 24-week long trial (7).

Weight loss has been reported as an adverse effect of fluoxetine treatment (6). In a one-year, placebo-controlled trial with fluoxetine, all patients gained weight, but the mean increase in weight did not differ from placebo (8). In Sweden fluoxetine is approved for treatment of bulimia (9).

In all above mentioned studies treatment with SSRIs have been used to treat major depressive disorder except for one (4) where the patients suffered from panic disorder.