New guidelines issued by the American College of Physicians says that “no substantial differences in efficacy or quality of life” have been found among second-generation antidepressants.

The guidelines, published in the Annals of Internal Medicine, come after the ACP reviewed more than more than 200 published studies about the benefits and harms of second-generation antidepressants. These included Eli Lilly’s Cymbalta (duloxetine) and Prozac (fluoxetine), GlaxoSmithKline’s Paxil/Seroxat (paroxetine) and Wellbutrin (bupropion) and Pfizer’s Zoloft (sertraline).

Amir Qaseem, senior medical associate in ACP's Clinical Programs and Quality of Care Department and the lead author of the guideline, said that “the studies we analysed show that second-generation drugs have different adverse effects but are equally effective for treating depression". He added that the ACP recommends that physicians make treatment decisions “based on side effects, cost and patient preferences”.

He added that doctors should make necessary changes in therapy if the response is not sufficient after six to eight weeks. They should also assess patient status and adverse effects on a regular basis “starting within one to two weeks of starting the treatment," Dr Qaseem noted.

The ACP notes that depressive disorders will affect about 16% of US adults in their lifetime and the economic burden is estimated to be about $83 billion. Dr Qaseem concluded by noting that “a loss of interest or pleasure from most daily activities, decreased ability to think or concentrate, or fluctuation in weight or sleeping patterns could be signs of depression”. If people experience these symptoms “for more than a few weeks, they should talk to their doctor", he said.