WASHINGTON -- About a quarter of women who stop taking hormone replacement therapy because of its risks wind up resuming the pills because of menopause misery, says the first research to explore how easy it is to quit.

Desperate for alternatives to alleviate hot flashes, more women are turning to certain antidepressants, such as Prozac and Effexor, that can offer some relief even if the users aren't depressed.

"They're very hot right now," says Dr. Nanette Santoro of the Albert Einstein College of Medicine. "Certainly in my clinical experience, they're the best second alternative" to estrogen.

Very few other options are backed by scientific evidence that they relieve what's considered menopause's worst symptom, hot flashes. Indeed, very few of the women who returned to hormone therapy had even tried an alternative, notes Dr. Deborah Grady of the University of California, San Francisco, who led the study about ease of quitting.

"One question that's important in my mind right now is how can we help these women?" Grady says.

It's a dilemma not just for women who suffer serious hot flashes for a few months surrounding menopause -- but especially for the 15 percent of women who keep having them for years.

"I just saw a woman who has a hot flash an hour," Dr. Jan L. Herr of Kaiser Permanente of Northern California says with a sigh. Hormone therapy had prevented them but the woman is scared to resume the pills, and reacted warily to Herr's suggestion of Prozac because she's not depressed.

Adds Santoro: "They seem overburdened with guilt and anxiety about continuing hormones, when to them the benefits of a good night's sleep and not turning into Rudolph the red-nosed reindeer every 10 minutes really are substantial."

Hormone therapy was long thought to protect postmenopausal women from such age-related conditions as heart disease and Alzheimer's. But sales have plummeted since July 2002, when a major study found hormone therapy in fact slightly raised users' risks of heart attack, stroke and breast cancer. That study examined combinations of estrogen and progestin; whether estrogen alone, used only by women who've had a hysterectomy, is as risky remains under study.

To see how difficult quitting is, Grady surveyed 377 randomly chosen Kaiser patients in northern California who tried. Roughly three-fourths of women will have either no or tolerable symptoms when they stop hormone therapy, she reported this month in the journal Obstetrics and Gynecology.

A quarter of the Kaiser patients had menopause symptoms, mostly hot flashes, return to such a degree that they resumed the pills. Tapering off didn't seem to help, although Grady stressed that most didn't taper slowly enough -- she advises six months to a year.

Women who really need estrogen, especially if they're otherwise at low risk of heart disease or cancer, shouldn't be scared away from it, Grady stresses.

Female doctors don't seem to be. A new poll of American College of Obstetricians and Gynecologists' members found half of female ob/gyns who are bothered by menopause use some form of hormone therapy themselves. Key is taking as little as possible for as short a period as possible.

But antidepressants like Effexor and those in the Prozac family help some women conquer hot flashes, an option that isn't widely known but is slowly gaining interest. There's no count of how many women try it, but in that ob/gyn poll, 13 percent of menopause-bothered doctors said they are.

Nobody knows why they work. But small studies suggest the antidepressants reduce hot flashes by about 60 percent, not as good as estrogen although better than other options so far have proved.

Doses are half or even less of the starting dose for depression treatment, so low that side effects mostly are decreased libido and some weight fluctuation, doctors say.

Other options:

--Trazodone, commonly used for sleep problems can help women whose hot flashes are worse at night and thus sleep-disrupting, Herr says. It's considered very safe; some women feel a hangover effect common with sedatives.

--Clonidine, a blood pressure medicine. The main side effect is blood pressure dropping too low.

--Black cohosh, an herb that's the most-touted estrogen alternative. Research is mixed on whether it actually works; a major study that may settle the issue is under way.

"Don't give up too soon," advises Santoro. "It's not necessary to live with symptoms that make you miserable."