BOSTON -- New antidepressants, like the drug Effexor, help millions of Americans fight depression and anxiety.

Video

Liz Brunner Reports On Drug Resources Effexor Web Site

NewsCenter 5's Liz Brunner reported there is growing concern about Effexor's side effects -- side effects that happen not when the patient is taking the drug, but when they try to stop.

When interior designer Teresa Winders started having panic attacks, her doctor prescribed Effexor.

"I didn't feel much better, and I was told, well, it takes four to five months to kick in. You've got to be patient," she said.

But Winders' symptoms continued to worsen, and eventually, she decided to slowly taper off the drug.

"You think at the beginning, OK, I can do this. And then you start to taper off, and you think you can't because you cannot feel your hands. And you cannot feel your feet," she said.

The side effects included severe muscle pain, nervousness and picking at her own skin to the point of major scarring.

Of the newer antidepressants, Effexor ranks No. 2 in sales, and studies show it provides important relief for many who take it. But it has a slightly different chemical makeup than other antidepressants like Paxil or Zoloft.

"The key difference is how quickly the drugs leave the body if you lower the dose," said Dr. Joseph Glenmullen. "Effexor is the fastest to leave, and causes the highest percentage of patients to have withdrawal."

Glenmullen, a Harvard psychologist and author of The Antidepressant Solution, said it can take six weeks to eight months to safely come off Effexor -- something he said is not widely known.

"Seventy percent of prescriptions for antidepressants are written by family doctors, many of them are not that aware of how bad withdrawal reactions can be," he said.

Effexor's maker, Wyeth Pharmaceuticals, does list a warning in the fine print of their insert that urges "a gradual reduction" and says, "patients should be monitored" during discontinuation.

Winders said more needs to be done to warn patients. In the meantime, she wondered how long it will be until her pain subsides.

"I'm officially disabled. I'm scarred for life," she said. "Will I always be in chronic pain? Will I ever be really happy again?"

In December, the United Kingdom issued stricter guidelines on Effexor. Now only specialists there can prescribe the drug.

A spokesperson for Wyeth said all antidepressants can lead to withdrawal symptoms and they stand by their warning labels and added it's the doctor's job to monitor patients carefully.