All About Weight Loss Drugs

Weight-loss drugs are medications designed to give you an extra push when motivation, diet and exercise fall short. Under a doctor’s supervision, these pharmaceuticals may be able to see you through a plateau when every other effort to reach your optimum weight does not yield the desired results. Obesity is a startling epidemic in the United States today, where an estimated $60 billion is spent on weight-loss products and services each year.

Anti-Obesity Medications generally work by:

  • Suppressing Appetite
  • Blocking the absorption of dietary fat
  • Increasing metabolism

Weight Loss Drugs

Most significant Weight Loss Drugs


Also known as Xenical, orlistat works by inhibiting fat digestion. It blocks the enzyme lipase, which is responsible for breaking down dietary fats to prepare them for bile and absorption. Undigested fat is not absorbed by your body, which reduces the amount of calories taken in. Orlistat has been shown to reduce body weight by up to10 percent when supplemented with diet and exercise. It also helps lower cholesterol and triglycerides as a side effect of decreased fat absorption.

Because the absorption of fat soluble vitamins like A, D and E is inhibited while you are taking orlistat, a multivitamin is generally recommended.  Another common side effect is frequent bowel movements and gas. If your diet provides insufficient fiber to bind with the undigested fat, you may experience anal leakage.


Also known as Meridia, sibutramine suppresses appetite by acting like the feel good brain chemical serotonin. Consistent levels of serotonin are associated with reduced sugar cravings and less tendency to overeat. In clinical trials of sibutramine, overweight subjects lost up to seven percent of their body weight.

The benefits of sibutramine may be outweighed by its side effects. Subjects reported symptoms that include increased blood pressure, dry mouth, insomnia, head ache, constipation, and stroke. It has been withdrawn from the market in the US, the UK, the EU, Australia, Canada and Hong Kong.


Also known as Metformin, Glucophage works by increasing insulin sensitivity. It also reduces inflammation in the liver. As a result, the hormonal balance needed to prevent PCOS (Polycystic Ovarian Syndrome) and other metabolic syndromes is preserved. Insulin working efficiently ensures that blood glucose levels in the bloodstream are consistent. By stabilizing blood sugar, the drug helps control sudden cravings and excessive hunger. Glucophage is widely prescribed in patients with Type 2 diabetes.
The side effects of Glucophage include gas and nausea. It is important to stay hydrated. Side effects increase during dehydration.


It is also known as Precose. It works the same way as the drug Orlistat. The only difference is that it works on sugars instead of fats. Acarbose works by blocking an enzyme needed in the metabolism of carbohydrates. Carbohydrates are prevented from breaking down in the gut and being absorbed by the body.
The side effect is that undigested sugars can cause diarrhea. Fermentation of undigested sugars can lead to more abdominal gas. Thus a diet high in fiber and low in sugars should be ideally taken when on this drug.


Also known as tegaserod, Zelnorm works by stimulating the serotonin receptors in your stomach. It increases the action of serotonin in the gut. Serotonin maintains your feel-good disposition and reduces cravings. The result is a controlled and reduced intake of calories.
Among patients who used Zelnorm, reports of abdominal pain and gas were widespread. The drug has been withdrawn from the market because of the associated side effects.


Rimonabant is primarily a cannabinoid (CB1) receptor antagonist. It works to suppress appetite by sending satiety signals to the brain. It also instigates thermogenesis to increase basal metabolism and burn a larger number of calories.
Rimonabant has not been approved by the FDA to be sold as a weight loss aid in the US yet.


U.S. Department of Health and Human Services, Food and Drug Administration; Weight-loss Drugs and Risk of Liver Failure; FDA.gov;

U.S. Department of Health and Human Services, Food and Drug Administration; Weight Loss Pills; FDA.gov;

Leave a reply

Your email address will not be published. Required fields are marked *