Brain wave activity is displayed by psychiatrist Daniel Maixner at the electroconvulsive therapy treatment area at the University of Michigan Health System in Ann Arbor. (Marty Slagter/Ann Arbor News via AP)

Correction: This article incorrectly identified the National Alliance on Mental Illness as the National Alliance for the Mentally Ill. This version has been corrected.

After years of consideration, the Food and Drug Administration has determined that for carefully selected patients with profound depression, the benefits of electroconvulsive therapy, long demonized, outweigh the risks of possible memory loss caused by its use.

Citing evidence from 60 randomized trials of ECT, once known as electroshock therapy, the FDA acknowledged the risk but said that there is now enough evidence to ease access to the therapy for certain people.

The devices that are used to administer ECT are regulated by the agency as Class III. That is the highest-risk designation, and it makes the equipment subject to the highest level of regulatory control. The FDA is proposing to downgrade that assessment to Class II for those whose depression has not responded to other treatments or is so severe that they need the kind of rapid response that only ECT can provide.

For other medical conditions — including catatonia, a stuporlike state of immobility for which ECT is considered by some psychiatrists to be one of the few effective treatments — the FDA said that too few randomized trials have been published to justify a Class II designation.

An estimated 100,000 of the 3 million people in the United States with treatment-resistant depression undergo ECT each year, a figure that could rise if the proposed new designation is finalized. By generating a brief pulse of electricity to the brain, the devices induce a generalized seizure. For reasons not fully understood, the result is that many patients feel better afterward.

If in fact finalized, the new assessment would bring to a close decades of wrangling over how best to regulate the controversial treatment. The FDA first proposed to classify ECT as Class II in 1978, before backing away after public opposition arose. It tried again in 1990 but did not finalize the change. In 2011, it invited an advisory panel to consider the issue yet again.

Following two days of contentious hearings, that panel voted, 10 to 8, against easing the classification, saying that not enough was known about the risks and benefits of ECT devices and that more research was needed.

Although the FDA generally follows the recommendations of its advisory panels, the agency finally decided against accepting that advice, publishing its proposal to ease the classification in the Federal Register on Dec. 28 of last year.

The change could go into effect at any point, because the three-month waiting period for public comment expired March 28. Deborah Kotz, an FDA press officer, said in an email that “the agency plans to review all the comments submitted to the public docket before making a final determination [on whether to move ahead] on the reclassification order.”

Prior to the advisory panel’s meeting in 2011, the FDA said it had received more than 3,000 comments from patients, family members of patients, researchers and others. About 80 percent of those comments opposed an easing of controls, the FDA reported late last year. Among the most common possible side effects mentioned by patients, the agency said, were memory loss, cognitive complaints and brain damage.

Thomas G. Brott, chairman of the 2011 panel and a neurologist at the Mayo Clinic’s campus in Jacksonville, Fla., said at the time that he opposed easing the classification because he could find no research into the effects of ECT based on MRI imaging, repeated brain wave (EEG) studies, or autopsy examinations.

“I tried to look and saw very little. I concluded that the evidence is not there to decide either way,” he said in 2011. He declined to comment on the FDA’s new action.

The agency’s recent review of published clinical trials found that the risk of death appears to be very low, similar to that seen with minor surgical procedures (about 1 per 80,000 treatments).

“The risks of greatest concern to clinicians and patients remain cognitive and memory impairment,” the agency stated. Its review found that it is not uncommon for patients to have difficulty forming memories in the hours and days following treatment but that this ability gradually “returns to baseline” within three months. Patients likewise see declines in recall ability immediately after treatment, but this too “appears to improve over time,” the agency stated. Even so, it noted, scientific data on memory loss beyond six months after treatment is lacking, and so it could not conclude that autobiographical memory returns to baseline over time.

To minimize those risks, the FDA has proposed some new controls on the use of ECT, including mandatory disclosure to patients of the potential for adverse outcomes. The agency also would impose new requirements for device labeling, testing, calibration and training, all designed to ensure that the devices function and are used properly.

Renée Binder, immediate past president of the American Psychiatric Association and a professor of psychiatry at the University of California at San Francisco, said she was in favor of the change. “What ECT is indicated for is the most severe type of depression, when nothing else has worked,” she said. “We’re talking about a person who is not eating, not sleeping. Many of these patients can’t go out of their home. This is a whole other kind of depression than most of us are familiar with. It’s disabling. Patients very commonly become suicidal. It’s a life-threatening illness.”

For such patients, Binder said, “ECT is the most effective and the most rapidly acting treatment. After a few ECT treatments, you can see a remarkable improvement in the patient’s mental state.”

The public’s dim view of the treatment is often traced back to a harrowing scene from the 1975 Oscar winner “One Flew Over the Cuckoo’s Nest.” In the film, Jack Nicholson portrayed a freewheeling, wisecracking criminal who thought he had pulled a fast one by getting himself sentenced to a psychiatric hospital rather than a prison. The brutal portrayal of his forcible treatment with ECT, held down by orderlies as his body violently convulses, has colored the public’s perception of the treatment ever since.

Binder said the film’s depiction of the treatment is outdated. Patients are now sedated and given muscle relaxants so that no bodily convulsions occur. A far lower dose of electricity is used than in decades past, only enough to incite a brief seizure. And patients’ informed consent is always necessary, as with any medical procedure.

Two members of the panel that recommended against easing restrictions on ECT said they had not heard of the FDA’s latest proposal until contacted by a reporter. “I wasn’t even aware of it, it’s taken so long,” said Guerry M. Peavy, a neuropsychologist at the University of California at San Diego who voted in 2011 to keep the high-risk classification. “It’s possible they got some new information I’m not aware of that might make them feel it’s safer.”

Christopher A. Ross, a professor of psychiatry at Johns Hopkins School of Medicine who voted in 2011 for reclassification, said he welcomed the FDA’s decision. “I think it’s a very effective treatment, and it can be lifesaving,” he said. “The risks of ECT are on a par with many drugs we use in psychiatry, and the benefits are often greater.”

Among those who testified before the panel in 2011 was Kitty Dukakis, wife of former Massachusetts governor and 1988 Democratic presidential nominee Michael Dukakis. She said that she had first received ECT as a treatment for her major depression 11 years earlier and had continued to get it once a month.

“It is not an exaggeration to say that I don’t think I would be alive without ECT,” she testified. “It has been a miracle in my life.” (She has continued to advocate for the therapy.) Other patients who spoke at the meeting, though, said the treatment had ruined their lives by robbing them of their memories.

The medical director of the National Alliance on Mentally Illness, an advocacy and support organization, said he supports the FDA’s reclassification as long as informed consent is emphasized as part of the process.

“I have had patients saved by ECT, I’ve seen it with my own eyes,” said Ken Duckworth, who also serves as an assistant clinical professor of psychiatry at Harvard Medical School. “But I’ve had people tell me that they might not have chosen ECT if they had known how it would affect their memory. So it’s really important that people have informed consent.”