Interim
Recommendations Issued For Patients
Exposed To Fenfluramine And Dexfenfluramine
The
U.S. Department of Health and Human Services issued preliminary
recommendations for the medical management of people who took
the diet drugs Fenfluramine or Dexfenfluramine. The recommendations,
published in the November 14, 1997 issue of Morbidity and
Mortality Weekly Report, were developed jointly by the Food
and Drug Administration, the Centers for Disease Control and
Prevention and the National Institutes of Health. As we enter
the new millennium, no changes to this recommendation has
been issued.
"Since these drugs were withdrawn from the U.S. market
in September 1997, many people who took them have been asking
what they should do, "said FDA's lead deputy commissioner
Michael Friedman, M.D. "We in the government, together
with the medical community, have developed these recommendations
to provide guidance based on the best information we have
at this time." The recommendations are based on current
knowledge about the association of these drugs with the development
of heart valvular disease.
The valvular damage can cause regurgitation--a backflow of
blood into a heart chamber--that may in some cases lead to
heart and lung disease. Of immediate concern for patients
with valvular disease is the possible increased risk of bacterial
endocarditis--an often serious and potentially fatal infection
of the heart's lining --following certain invasive medical
and dental procedures. Until more complete information is
available, HHS recommends the following measures for people
who have taken Fenfluramine or Dexfenfluramine.
* Anyone who has taken Fenfluramine or Dexfenfluramine for
any period of time, either alone or with another drug or drugs,
should see their doctor for a medical history and physical
examination to determine whether there are signs or symptoms
of heart or lung disease.
* Anyone who has taken these drugs for any period of time,
either alone or with another drug or drugs, who has signs
or symptoms of heart or lung disease, such as a new heart
murmur or shortness of breath, should have an echocardiogram
performed.
* An echocardiogram should be strongly considered for any
patient who has taken these drugs, either alone or with another
drug or drugs -- regardless of whether they have signs and
symptoms of the heart or lung diseases -- BEFORE having any
invasive procedure for which the American Heart Association
recommends antibiotic prophylactic treatment to prevent the
development of bacterial endocarditis. This will provide an
accurate determination of whether or not the person needs
the antibiotic treatment.
These interim recommendations may be updated as new information
becomes available. On September 15, at the request of the
Food and Drug Administration, Wyeth-Ayerst Laboratories and
Interneuron Pharmaceuticals, which manufactured and marketed
Fenfluramine under the brand name Pondimin and Dexfenfluramine
under the brand name Redux, voluntarily withdrew these products
from the market.
The withdrawal was based on initial echocardiographic findings
in five surveys indicating that approximately 30 percent of
patients in these surveys who took these drugs had valvular
abnormalities, even though most had no symptoms. This is apparently
much higher than would be expected in the general population,
where additional preliminary reports suggest that significant
valvular regurgitation occurs in less than five percent of
the general population of young and middle-aged adults in
the United States.
Studies are underway and others planned to learn more about
the clinical significance of these findings, the natural course
of the valvular lesions (that is, whether they generally disappear,
become worse, or stay the same once the drugs are stopped),
and what factors, if any, may increase an individual's susceptibility
to their development.