Anti-obesity drugs are the
pharmaceutical
formulations intended to reduce or control weight. When the body mass
index (BMI) of a person is 30 or more, s/he falls in the category of
overweight obese population. Overweight and obesity are diseases where an
excess of body fat accumulates in such a way that may adversely affect
health. Anti-Obesity Drug is administered to overweight people who fail in
achieving weight loss support from other means. Best weight loss program is
considered to be a combination of supervised balanced diet, physical
exercise and lifestyle modification. However, Anti-obesity drugs are used in
adult obesity patients who do not get success in achieving a 10% weight
reduction after at least three months of supervised care.
Anti Obesity Drug Therapy
An anti-obesity drug therapy is
prescribed for a maximum of 12 weeks in the first instance. Thereafter
weight loss is measured. Most of the time, the drug treatment is stopped
where the obese patients do not achieve a 5% weight reduction after 12 weeks
of drug treatment. If a 5% or more weight loss is attained then the drug is
continued. Body weight is continually monitored to check regain of weight.
Types of Anti-Obesity Drugs
There are two main categories of anti-obesity drugs
- Anti obesity drugs that act on the gastrointestinal system
(pancreatic lipase inhibitors)
- Anti obesity drugs that act on the central nervous system mainly to
suppress appetite
Orlistat is an example of the first kind of anti obesity drug that
inhibits pancreatic and gastric lipase. It decreases ingested triglyceride
hydrolysis that produces a dose-dependent reduction in dietary fat
absorption which in turn leads to weight loss.
Sibutramine is the example of second kind of anti obesity drug that
promotes a sense of satiety through its central action as a serotonin and
norepinephrine re-uptake inhibitor. It may also mitigate against the fall in
thermogenesis through stimulation of peripheral norepinephrine receptors. It
is, in simple terms, an anorectic or appetite suppressant, that reduces the
desire to eat.
Rimonabant is a recently developed anti-obesity drug. It also acts
centrally on the brain and decreases appetite. It may also act peripherally
by increasing thermogenesis and therefore increasing energy expenditure.
Other anti-obesity prescription drugs include Bontril (phendimetrazine
tartrate), Desoxyn (methamphetamine) and Ionamin and Adipex-P (phentermine).
There are many anti obesity drugs but some of them have severe or
life-threatening side effects. Therefore, they are recommended to be taken
only under medical supervision. Prescription weight loss drugs are approved
only for those with a BMI of 30 and above, or 27 and above if they have
other risk factors, such as high blood pressure or diabetes.