Drugs approved by the FDA for weight loss

Drugs approved for use in weight loss programs can be broken down into the following categories:

1. Anorexiants (drugs that work on chemicals in the brain)

a. Amphetamines

1. Benzphetamine (Didrex)
2. Diethylpriopion (Tenuate ; Tenuate Dospan )
3. Methamphetamine (Desoxyn)
4. Phentermine (Adipex; Adipex-P or Ionamin )

b. Sibutramine (Meridia )

2. Lipase Inhibitors (drugs that prevent fat from being absorbed into the bloodstream)

a. Orlistat (Xenical)

Drugs that work in the brain are considered appetite suppressants. Amphetamines are approved for use in treating other diseases; their use as a weight loss drug is considered “off label” or not approved. Doctors often prescribe drugs for “off-label” use, meaning that the drug is used at a different dose, for a longer time, or for a different medical condition than was approved by the FDA. Off-label prescribing is a common, and legal, practice.

Amphetamines, which have appetite-suppressing effects, are approved by the FDA for weight loss, but only for short-term use (12 weeks or less). Only a handful of studies have evaluated their use for periods longer than six months. Scientists do not fully understand how amphetamines and amphetamine-like drugs work. It is believed that these drugs cause the release of norepinephrine and dopamine, two chemical messengers that control hunger, in the brain. In addition, it is thought that amphetamines decrease the sharpness of a person’s senses of smell and taste, which ultimately results in appetite-suppressing properties.

Another benefit of amphetamines is that they allow someone who is obese or overweight the opportunity and time to learn proper weight loss techniques, such as diet and exercise. Because they are addictive, amphetamines are not often recommended for use in weight loss. Amphetamines and amphetamine-like drugs only bring about a very small amount of weight loss (3–8% decrease in weight when compared to placebo). So, since amphetamines are addictive and not very effective for long-term weight control, they are not recommended for weight loss.

Amphetamines and amphetamine-like drugs only bring about a very small amount of weight loss. The usual weight loss that occurs is only 5 to 10 pounds. Often, the weight loss effects only last for a few weeks. The way these drugs help induce weight loss is by providing the patient the time and opportunity he or she needs to learn proper weight loss techniques.