Nearly nine thousand people wrote in to the New York Times last week to share their experiences of withdrawal from long-term antidepressant use. Many said their attempts to stop taking drugs like Paxil, Prozac, and Zoloft resulted in fatigue, headache, dizziness, flu-like symptoms, night sweats, tremors, panic attacks, and mood swings. Several reported an electric shock sensation they referred to as “brain zaps.”

“I have cut down from 200 milligrams to 100,” wrote one typical respondent to the reader query, “but when I go lower I get horrible side effects, like nausea, jumpiness, crying a lot which I never do. I’m nearly 75; at this point I will continue because I cannot go through the withdrawal.”

A week prior, the New York Times published its analysis of the available federal data on long-term antidepressant use. Researchers found that in the United States 15.5 million people have been taking antidepressants for more than five years, a number that has more than tripled since 2000. 25 million people have been taking them for more than two years. That’s nearly 8 percent of the United States at risk of these prohibitive withdrawal symptoms.