Obesity Treatment Medication

Weight loss medication does exist, but its use as a treatment for obesity is somewhat limited. Medication for obesity produces long-term weight loss only if used in combination with lifestyle and dietary changes.

When to Use Medicine for Obesity

Medication for obesity is used for rapid weight loss in circumstances when obesity causes health complications. Medicine for obesity may also be used to support diet and exercise treatments.

In most cases, weight loss medication is only prescribed if a person has a BMI higher than 30. People with a BMI between 25 and 30 may be prescribed obesity medication if they also have weight-related health problems such as hypertension.

Obesity Medication Limitations

Weight loss medication can improve treatment of obesity, but it’s important to remember that medication for obesity has some limitations. Any benefits of medicine for obesity will be lost when the medication is stopped, unless other treatments are also used. Combining weight loss medication with exercise and changes in eating habits is more successful than treating obesity with medication alone.

Weight loss medication has the potential to be abused, especially amongst people with eating disorders. Long-term use of medication for obesity may also produce a tolerance for the medication, causing the medication to become less effective over time.

Types of Medication for Obesity

Only two types of weight loss medication are approved for long-term use by the U.S. Food and Drug Administration: sibutramine and orlistat. These two medicines for obesity work in very different ways.

Sibutramine is an appetite suppressant that may also have antidepressant qualities. Sibutramine affects the brain chemicals serotonin and norepinephrine, which regulate appetite and mood.

Sibutramine should not be prescribed to pregnant women, women who are breastfeeding or those under the age of 16. People using prescription pain relievers, other weight loss medication and some types of antidepressants should avoid sibutramine. A history of hypertension, heart disease and strokes also contraindicates sibutramine use.

Side effects of sibutramine include:

  • Anxiety
  • Constipation
  • Dizziness
  • Dry mouth
  • Headaches
  • High blood pressure
  • Stuffy nose
  • Trouble sleeping.

Orlistat works by partially blocking the digestion of dietary fat. Undigested fat is removed in bowel movements. Because orlistat also reduces digestion of fat soluble vitamins, doctors may prescribe a multivitamin supplement to ensure proper nutrition. As with sibutramine, pregnant or breastfeeding women should avoid orlistat, as should people with gallbladder problems or problems absorbing food.

Orlistat side effects include:

  • Gas with discharge
  • Increased bowel movements
  • Oily discharge
  • Oily stools
  • Temporary loss of bowel control.

In addition to sibutramine and orlistat, the prescription weight loss medication phentermine is sometimes used for short term weight loss. Combinations of phentermine and dexfenluramine were popular as a weight loss medication in the 1990s. The combination, known as “phen-fen,” was found to cause heart and lung problems and is not longer used. Although phentermine is still available in the United States, this medication may cause similar complications even when not combined with fenluramine.


Cleveland Clinic. (n.d.). Obesity medications. Retrieved April 25, 2010, from http://www.clevelandclinic.org/health/health-info/docs/2400/2468.asp?index=9475