Sibutramine
(Brand names: Meridia in the US or Reductil in other countries)
These medicines block the nerve signals called
norepinephrine,
serotonin,
and
dopamine from
being taken back up by the signaling nerves. This means that receiving
nerve cells are exposed to these signals for a longer period of time.
Norepinephrine, serotonin, and dopamine are neurotransmitters used by a
branch of the nervous system called the
sympathetic nervous system.
More stimulation by these chemicals causes a decrease in appetite. This
causes people to eat less. Sibutramine (Meridia or Reductil) has a
chemical structure related to
amphetamine.
It works in a somewhat similar manner.
Pros
Studies
have shown that on average, people lose weight with Meridia.
Within 1 year, there may be a 9.8 lb (4.45 kg) weight loss. One study
showed that sibutramine in combination with lifestyle changes caused a
weight loss of 26.6 lbs compared to the drug (11 lbs) or lifestyle
changes (14.8 lbs) alone.
There also
appears to be a reduction in
triglycerides
and
bad (or LDL)
cholesterol.
People with
diabetes
may see a decrease in their blood sugar (glucose) and
hemoglobin A1c levels (a longer term measure of blood sugar control). Diabetics may also see an increase in their
good (or HDL)
cholesterol. Meridia causes weight loss in adolescents.
Cons
Meridia increases blood pressure by 1-3 points (mmHg) and heart rate by about
4-5 beats per minute. Diabetics need good control of their blood
pressure in order to prevent kidney or other organ damage. In one study
among adolescents, the dose of sibutramine had to be decreased or the
drug had to be stopped because of increases in blood
pressure or heart rate. The effect on increased blood pressure is most
in people weighing 203 lbs or more and in people younger than 44 years
old.
This drug should be avoided in people with
coronary heart disease (CHD
or CAD),
congestive heart failure (CHF),
heart rhythm problems,
or people who have had a
stroke.
There is a risk of developing something called
serotonin syndrome
in people who take Meridia along with a
monoamine oxidase inhibitor (MAOI)
or
selective serotonin reuptake inhibitor (SSRI),
both of which are mainly antidepressants but can be use for other
conditions. Erythromycin, ketoconazole, or other medicines that affect
the enzyme
cytochrome P450 (CYP450)
can affect the body’s metabolism of sibutramine. You should discuss all of this with your doctor.
By
2004, in a hearing that prompted the withdraw of Vioxx, an FDA officer
testified to the US Senate that sibutramine was potentially dangerous.
Meridia is a schedule IV prescription drug. This means there are
more restrictions on its use.
Other Comments
In
nearly all studies, giving the drug was also accompanied by making a
change in the person’s diet. Diet and exercise are the cornerstones of
any weight loss program.
This is a
drug with several risks and some benefits. It is important that you
thoroughly discuss this medicine with your doctor before deciding on
using it. One review of this medicine even recommends against its use.
Return to
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or
Home Page.
It is important you discuss any weight
loss or exercise plan with your doctor. Only you and your physician can
decide what is best for you. Some people have certain conditions that
prevent them from doing all exercises, and goal body weights may be
different for different people. You need to discuss all these things
with your physician before starting any weight loss or exercise program.
This article was written by
John Vickery, MD.
References
Ann Intern Med 2005;142:525-531
“Drug therapy of Obesity” Up To Date version 15.3
The Medical Letter on Drugs and Therapeutics 1998;40:32
The Medical Letter on Drugs and Therapeutics 2004;46:97
NEJM 2008;358:1941-50
