Last week the Food and Drug Administration asked the manufacturers of the popular diet drugs fenfluramine and Redux to withdraw their products, citing "an unacceptable risk" of heart valve problems. The agency also advised consumers to stop taking the drugs and to contact their doctors.
Users of fen-phen (a combination of fenfluramine, sold as Pondimin, and the drug phentermine) and Redux faced many unanswered questions. Among them:
Question: Which is better, to taper off or to quit these drugs cold turkey?
Answer: "I think it's better to taper off over a week or so," says Dr. Richard L. Atkinson, professor of medicine and nutritional sciences at the University of Wisconsin, Madison, and president of the American Obesity Assn. But he hastens to add: If you've already quit cold turkey, don't start up again.
Adds Dr. Morton Maxwell, clinical professor of medicine and director of the University Obesity Center at the UCLA School of Medicine: "In the literature, it has been reported that in some patients after stopping fenfluramine [abruptly] they can become mildly depressed for a week or so." But, he says, many patients in the UCLA program, for example, have forgotten to bring the drug on vacation with them and have not had serious problems.
Q: What kind of physical exam and other tests do I need?
A: Your doctor should take a thorough medical history and conduct a physical with an emphasis on examining the heart and lungs, says Dr. Richard Kerber, professor of medicine and director of the echocardiography lab at the University of Iowa, Iowa City, and president of the American Society of Echocardiography.
Your doctor should listen to your heart with a stethoscope as you lie down, bend over and possibly assume other positions, says Kerber.
If there is any suspicion of heart valve problems, your physician should order an echocardiogram, a diagnostic procedure that uses high-frequency sound waves, or ultrasound, to take moving pictures of the heart.
If your doctor does not think an echocardiogram is needed, you should return for follow-up exams at intervals to be decided based on medical history and other factors, says Atkinson.
Q: If there is heart valve damage, won't I have symptoms?
A: "Not necessarily," says Dr. Jack Crary, an interventional cardiologist at MeritCare Medical Center in Fargo, N.D., and a coauthor of the study published last month in the New England Journal of Medicine that aroused wide-spread concern about fenfluramine's effect on the heart. Some people have no symptoms, he says; others have shortness of breath or chest pain. If there's any doubt, "the best way to detect [problems] is with an echocardiogram."
(The FDA's action was spurred in part by its analysis of 291 patients, in which 30% had abnormal echocardiograms, even though they had no symptoms. In most, the problem was a so-called leaky valve.)
Q: What does an echocardiogram involve?
A: Before the test, no special preparations such as fasting are normally required, according to the American Society of Echocardiography. During the test, you'll be asked to disrobe from the waist up so a transducer--a small, hand-held device--can be placed on the chest wall or upper abdomen in order to direct sound waves to the heart and produce pictures of it. The images appear on a TV-like screen and are recorded on videotape as well as on special paper.
An electrocardiogram is also routinely done during an echocardiogram because it is useful for timing the events in the heart.
The echocardiogram can measure the size of each of the heart's four chambers and can study the appearance and motion of the heart valves. It can also determine how forcefully the heart muscle contracts to move blood into the chambers and to the lungs and the rest of the body.
It takes about 45 minutes to do a complete echocardiogram, Kerber says. "If your doctor thinks one is necessary, I would advise a complete exam [rather than a limited one]."
But sometimes a physician may opt to do a limited study, Kerber says, if there is already an initial, or baseline, echocardiogram for comparison.
Q: What does an echocardiogram cost?
A: In the Los Angeles metropolitan area, the test can cost as much as $1,500.
Q: Is the cost likely to be covered by my health insurance policy or health maintenance organization plan?
A: Plans vary.
At Kaiser Permanente, for example, "an echocardiogram considered necessary by a Kaiser Permanente physician is a covered benefit," says Kathleen Barco, a spokeswoman, although some members may have to make a small co-payment.
"Coverage for HMO members [who need an echocardiogram] will be decided on an individual basis," according to Rhonda Seaton of Blue Cross of California. Those Blue Cross members who have a PPO and need an echocardiogram would be covered for it "just as any other service." For instance, if they normally pay a deductible and 20% of the cost, the same would be true for the echocardiogram.
Q: Do I need to have a physical exam if I only took fen-phen for a short period of time, say a few weeks or months?
A: If you took the drug for "any period" of time, says Atkinson, it's a good idea to be examined.
Q: What's the prognosis if I have heart valve damage?
A: Physicians are still trying to figure that out.
Crary has prescribed blood pressure medications so "the blood flow is directed more upstream than backward." It doesn't correct the underlying problem [with the valve] but "things improve."
Whether the valve problems will go away in time, Crary says, "remains to be seen."
Some physicians say their patients on fen-phen with heart valve damage appear to have healed after stopping the pills.
In other diseases involving the heart valves, such as mitral valve prolapse, the underlying damage to the valve does not change over time, says Dr. P.K. Shah, director of cardiology at Cedars-Sinai Medical Center. Whether valve problems associated with diet drug use are reversible, he says, is not yet certain.
Follow-up is crucial. "In the absence of symptoms," Shah says, "we generally follow patients with significant [valve] leaks every six to 12 months. But this [phenomenon] is so new, there are many unknowns."
Some patients have only a minor problem with leaky valves, Crary has found, where others have valves that are severely impaired.
Q: Is there any danger to exercising now if I have just stopped taking fenfluramine or Redux?
A: Asking your doctor is the best answer, experts concur.
Q: What are the alternatives now that fenfluramine and Redux are off the market?
A: Opinions vary.
It's crucial for dieters to remember that drugs should not be the mainstay of any weight-reduction program, says UCLA's Maxwell, whose program also emphasizes behavior modification, exercise and calorie reduction.
"We are continuing our [fen-phen] patients on the phentermine," Maxwell says. Phentermine has not been implicated in heart problems. But some patients on phentermine alone may have restlessness, insomnia or nervousness. In that case, Maxwell says, "we may add a medicine such as a mild sedative."
Herbal Phen-Fen, a combination of the herb St. John's wort and the stimulant mahuang will continue to be offered at Nutri/System and its affiliate, U.S. Medical Weight Loss Clinics, says Joseph DiBartolomeo, vice president of scientific affairs. It's not known yet whether the name will be changed. The centers are also offering phen-Pro, a combination of phentermine and the antidepressant Prozac.
Q: What's the next big diet drug?
A: The next prescription diet drug expected to hit the shelves is sibutramine Meridia. "We anticipate approval by the FDA this year," says Linda Mayer, a spokeswoman for Knoll Pharmaceutical Co.
How does it work? Basically, it makes you satisfied with less food and in animal studies has boosted metabolism, Mayer says.
G. Ken Goodrick, an obesity expert at the Baylor College of Medicine who is familiar with research on the drug, says it has a "pretty good safety profile."