US FDA warns of new antidepressant risks

WASHINGTON, July 20 (Reuters) Migraine sufferers and newborns face possible life-threatening risks linked to some of the world's most widely used antidepressants, the US Food and Drug Administration has said.

Combining some antidepressants including Prozac and Zoloft with certain migraine drugs known as triptans could result in a life-threatening condition called serotonin syndrome, the FDA warned.

The agency also warned about a possible fatal lung condition in newborns whose mothers take certain antidepressants while pregnant yesterday.

The warnings follow earlier concerns that antidepressants may increase the risk of suicidal behaviour in children and teens a warning already on drug labeling.

Serotonin syndrome, caused by excessive amounts of the neurological chemical, can trigger hallucinations, a rapid heartbeat and overactive reflexes, among other problems.

Patients should talk to their doctors about deciding whether to continue taking the antidepressants, which include a class of drugs called SSRIs and two SNRIs, the FDA said. It also asked drug makers to include the risk on drug labels.

SSRIs, or selective serotonin reuptake inhibitors, include GlaxoSmithKline Plc's Paxil, Eli Lilly and Co's Prozac, Pfizer Inc's Zoloft and Symbyax, Forest Laboratories Inc's Celexa and Lexapro, and Solvay Pharmaceutical's Luvox, and generic equivalents.

The SNRIs, or selective serotonin/norepinephrine reuptake inhibitors, cited by the FDA are Lilly's drug Cymbalta and Wyeth's Effexor.

Triptan migraine drugs include Glaxo's Imitrex and Amerge, Johnson&Johnson's Axert, Endo Pharmaceutical's Frova, Merck and Co Inc's Maxalt, Pfizer's Relpax and AstraZeneca Plc's Zomig.

The FDA also said there was a risk of persistent pulmonary hypertension in newborns whose mothers took SSRIs during pregnancy.

The agency said it was seeking more information and would update the labels as necessary.

Regulators' concerns follows a February study in The New England Journal of Medicine that found those taking SSRIs were six times more likely to have a baby suffering from the condition in which high blood pressure in the lungs makes it hard to breathe.

The agency advised women who are pregnant or thinking about becoming pregnant to talk to their doctors about deciding whether to continue taking an antidepressant.

''The decision to continue medication or not should be made only after there has been careful consideration of the potential benefits and risks of the medication for each individual pregnant patient,'' the FDA said.

Patients also should be closely monitored to see if their depression returns, the agency added.

REUTERS SP BD1028