F.D.A. Orders Warning on All Estrogen Labels

The Food and Drug Administration announced yesterday that all companies making drugs that contain estrogen or estrogen and progestin for menopausal women must include a boxed warning on labels stating that the drugs may slightly increase the risk of heart attacks, strokes, blood clots and breast cancer.

The agency said that since a large federal study concluded last summer that Prempro, a drug made by Wyeth, slightly increased those risks, it must be assumed that all other products containing estrogen, including patches, creams and pills, have similar problems unless proved otherwise.

Until now, only Prempro's label mentioned the risks, which were stated in boldface type on the label but were not in a box. The company changed its label in August to include the risks after findings from the federal study, the Women's Health Initiative. The company also sent letters to a half-million doctors informing them of the results.

The study found that the risks from the drugs were not outweighed by their benefits, a slight reduction in bone fractures and colon cancer. Prempro's warning will now also be in a black box, and the company is mailing additional letters to doctors informing them of the drug agency's action.

The study's findings shocked many women and their doctors, who had assumed that Prempro, which was the most popular estrogen-containing drug used by menopausal women, was simply replacing the lost hormones of youth. Prempro's sales have since dropped by 50 percent, said Doug Petkus, a Wyeth spokesman.

But many women want to continue taking estrogen because it is the most effective treatment for symptoms of menopause, like hot flashes, night sweats and vaginal dryness. Others have wanted estrogen because they believe, in the absence of rigorous evidence to show it, that estrogen improves memory and smooths the skin. So, after the risks of Prempro became known, many switched to other estrogen products.

But the drug agency's commissioner, Dr. Mark McClellan, said yesterday that "there is no reason to believe that any other drug is safer than Prempro." He added: "We want similar labeling on all these products. At the moment we don't have the information to say that one or the other is different."

There are 5 products on the market that contain estrogen and progestins and 15 that contain estrogen alone, the agency said.

Kim Schillace, a spokeswoman for Berlex Laboratories, a Montville, N.J., company that makes an estrogen patch, said that the company would work with the agency on revising its label. "We will have to make changes, but we have to determine what those changes will be," Ms. Schillace said.

But with 10 million women in this country still taking estrogen products, the agency's decision sends a strong message, medical experts said. Putting a black box on a drug's label is a regulatory action, and it is not taken lightly.

"Having a black box on the label is a big deal," said Dr. Susan Hendrix, a gynecologist at Wayne State University in Detroit who was an investigator in the federal study. "It's pretty astounding to go from a year ago thinking this is one of the most benign drugs to a 180-degree turn in the opposite direction."

Dr. McClellan said that women should consult with their doctors about whether to take estrogen for the symptoms of menopause. But, he said, "estrogen and progestin should be used at the lowest doses for the shortest time."

The agency has also revised two of the three indications for the use of estrogen. The drugs were suggested for vaginal dryness and irritation, even if there were no symptoms and the condition was noticed only in a medical exam. Now, the drugs' labels will state that the condition must be moderate to severe and that women should consider using topical products, like vaginal creams.

Although estrogen can slow bone loss that occurs with menopause, the new drug labels must state that when the hormone is used only for prevention of osteoporosis, it should be restricted to women who are of the highest risk. Even then, the new labels will say, other osteoporosis drugs that do not contain estrogen should be considered.

Estrogen is still recommended to alleviate moderate to severe hot flashes and night sweats. "These symptoms can be very disruptive and are often only controlled by estrogen," Dr. McClellan said.

Many medical authorities applauded the drug agency's decision.

Dr. Isaac Schiff, a gynecologist at Massachusetts General Hospital, said that a task force he led for the American College of Obstetrics and Gynecology had advised doctors not to assume that other estrogen formulations were any safer than Prempro. But, Dr. Schiff said, "some distinguished people in my discipline, I am embarrassed to say, put out a letter saying the patch is safer."

Now, he said, it should be harder to make that argument. "Some doctors who were so positive about estrogen are put on notice," Dr. Schiff said. "They can't say other products are safer."

Dr. Wulf Utian, the executive director of the North American Menopause Society, said his group also advised doctors not to assume that other estrogens are safe, but that many continued to believe that the safety problems were only with Prempro.

"I think it is really quite significant that the F.D.A. is generalizing to all products," Dr. Utian said. "They recognize that you can't assume safety. If you want to say you are a safer product, you have to do the studies."