Updated

Although antidepressants are effective in children, they are known to increase suicidal behavior. That increase, however, is not dependent on the specific drug, researchers reported on Monday.

Examining a wide range of antidepressants — including fluoxetine (Prozac), sertraline (Zoloft) and paroxetine (Paxil) — they found similar rates of suicide and suicide attempts in more than 20,000 Canadian youth.

"The main finding is essentially a non-finding, meaning that there is no difference in risk for a suicide between different drugs," said Dr. Sebastian Schneeweiss of Harvard Medical School, who led the research, published in the journal Pediatrics.

"That is extremely important to know, because then you can focus only on the effectiveness of antidepressant drugs," he added.

The US Food and Drug Administration currently requires a "black box" warning on antidepressant labels that draws attention to the increased risk of suicidal thoughts and behaviors in kids and young adults who take the drugs.

What hasn't been clear, however, is whether some drugs are safer than others.

Schneeweiss and colleagues found three suicides and 266 unsuccessful suicide attempts among 10- to 18-year-old Canadians who had taken antidepressants for a year. Considering how long each person had been on antidepressants, that corresponds to about 3 suicides per year if 10,000 are treated.

While this rate is about five times the rate in the general population of teens in British Columbia, where the data was collected, the suicide risk was similar for different types of antidepressants. These included selective serotonin reuptake inhibitors (SSRIs) — the most commonly used drugs such as Prozac — and older drugs.

"The new study includes a far wider range of antidepressants than were included in earlier studies," psychiatrist Dr. Mark Olfson of Columbia University, who was not involved in the study, told Reuters Health in an e-mail.

He added that the results suggest doctors and patients shouldn't worry as much about safety when comparing antidepressants. Instead, he said, they should concentrate on how well the drugs work.

Because of the increased suicide risk in children and adolescents, it is still important to keep a close eye on young patients, said Dr. Thomas Laughren, director of the FDA's Division of Psychiatry Products. But, he added, "being vigilant is different than being afraid."

"The fact is, most people treated with these drugs get better," he told Reuters Health.