A popular acne-fighting drug that has been linked to birth defects and is being monitored for ties to suicide did not cause depression in a group of adolescents, a study has found.

Roche’s Accutane, which is also sold in generic versions as isotretinoin, was given to 59 patients and their overall incidence of depression declined.

There were only a few new cases of depression that showed up among those taking the drug, about the same as in a control group receiving a more conservative acne therapy, the study published in the Archives of Dermatology said.

“The use of isotretinoin in the treatment of moderate-severe acne in adolescents did not increase depressive symptoms. On the contrary, our study shows that treatment of acne improves depressive symptoms,” wrote study author Dr. Christina Chia of Saint Louis University Health Sciences Center in St. Louis.

She echoed previous arguments by the drug’s manufacturer and some other researchers that acne itself can be a cause “significant psychological stress.”

The U.S. Food and Drug Administration is monitoring the drug to determine if it causes depression and suicide. The agency also ordered creation of a registry to ensure pregnant women, or women who may become pregnant, do not take it because of a risk of birth defects.

Accutane was one of five drugs cited by veteran FDA scientist David Graham at a congressional hearing last year as approved drugs that ought to receive closer scrutiny.

The controversy over Accutane grew out of a wrongful death lawsuit involving a young pilot who was taking the drug and crashed his small plane into a building in Tampa, Florida, in 2002.

Critics say the drug, which has been taken by millions, is over-prescribed for mild acne cases.

In the current study, 132 subjects aged between 12 and 19 were tested for depression before and three or four months after taking the drug. In the group who took the drug, the percentage found to be depressed dropped to 8 percent from 14 percent. The depression rate in the control group stayed about the same.

In a separate study published this month in the American Journal of Psychiatry, brain scans on adults taking the drug showed a decrease in brain metabolism in an area of the frontal cortex that is associated with mediating depressive symptoms.

The study concluded that the drug can cause depression in a small percentage of people and suggested screening for psychiatric disorders before it is prescribed.