The Food and Drug Administration sharply stepped up warnings about possible risks to patients taking antidepressant drugs, asking doctors, families and caregivers watch closely for signs of increasing depression or suicidal thinking.

The FDA asked the makers of 10 major antidepressant drugs, including versions of Prozac, Wellbutrin, Paxil, Effexor and Zoloft, to place more detailed, explicit warnings on the labels for their medicines. The FDA didn’t order the manufacturers to change their labels, but urged them to do so voluntarily. The new cautions would ask doctors to monitor patients for a variety of symptoms from insomnia and irritability to hostility and panic attacks that might possibly signal greater risks.

The announcement comes more than a month after an FDA advisory committee urged the agency to provide clearer warnings about possible risk of suicidal tendencies in children and adolescents taking antidepressants. Still, yesterday’s development went well beyond the earlier recommendations, and included adults as well.

The most immediate result may be that doctors, particularly those who don’t focus on pediatric psychiatry, become more cautious in how they prescribe antidepressants for kids and teenagers. They could start prescribing smaller doses and being slower to step up the amounts of medicine.

“People might wait until they’ve been in talking therapy a little bit, before trying drugs,” said Richard Malone, a child psychiatrist at Drexel University College of Medicine, who was a member of the FDA advisory committee.