Some antidepressants are more effective than others
- Alan Lenox-Smith, Senior medical adviser for central nervous system productsa
- a Wyeth*, Taplow, Maidenhead, Berkshire SL6 0PH
- b St George's Hospital Medical School, London SW17 0RE
- c Oxleas NHS Trust, Bexley Hospital, Bexley, Kent DA5 2BW
- d Academic Unit of Psychiatry, United Medical and Dental Schools, St Thomas's Hospital, London SE1 7EH
Editor—I challenge Pathare and Paton's statement that “All antidepressants are equally effective in treating depression.”1 There is growing evidence that antidepressants that block the reuptake of both serotonin and noradrenaline have greater clinical efficacy than those that act on just one neurotransmitter.
Patients with mild depression often show a high rate of response to placebo, and differences between drugs can be hard to detect. Differences will (usually) be shown only when patients with moderate to severe depression are studied. Another way to look for differences between drugs, or classes of drugs, is to combine trials to gain statistical power in a meta-analysis.
It is important to look at the different classes of drug that block the reuptake of serotonin and noradrenaline. Such drugs comprise the older tricyclic antidepressants, which can be subdivided into those that have their main action on noradrenaline (for example, desipramine) and those that have their action on both serotonin and noradrenaline (for example, clomipramine); the selective serotonin reuptake inhibitors (for example, paroxetine and fluoxetine), which block the reuptake of serotonin only; and the newer class of serotonin and noradrenaline reuptake inhibitors, which block the reuptake of both serotonin and noradrenaline.
Early suggestions that drugs with dual action had advantages over those that increased just one neurotransmitter came from the Danish University Antidepressant Group,2 which …