How It Works
Sibutramine changes the levels of chemicals in the brain, including serotonin. Serotonin is a neurotransmitter, which is a type of chemical that sends messages back and forth in the brain. These brain chemicals are thought to influence feelings of hunger and fullness. Sibutramine (Meridia) works by making you feel full sooner when you eat.
Why It Is Used
Sibutramine is prescribed to help people who are obese (those with a body mass index [BMI] of 30 or higher) to lose weight. In some circumstances, it may be prescribed for people with BMIs of 27 to 30 when they have other conditions, such as diabetes or sleep apnea, that are made worse by being overweight. It may also be useful in treating binge eating disorder. Sibutramine is intended to be used along with a weight-loss diet and a regular exercise program.
How Well It Works
One study shows that about 60% of people who took sibutramine for 1 year had a 5% weight loss .1 A review of studies found that people who took sibutramine lost an average of about 10 lb (4.5 kg) more than those who took a placebo.2
Another review of studies on sibutramine found that it results in weight loss not only in otherwise healthy people who were obese but also in people who were obese and had type 2 diabetes and high blood pressure
Sibutramine doesn't work for everyone. About 10% of those who use it do not lose weight while taking the medicine. If you have not lost about 4 lb (1.8 kg) within the first month of treatment, sibutramine may not be an effective medicine for you.3
Side Effects
Side effects may include:
- Increased blood pressure. In most people, the increase is small enough not to be a cause for concern. But in others, the increase may be large enough to reconsider use of the medicine. Also, as you lose weight, your blood pressure may come down.
- Increased pulse (heart rate).
- Headache.
- Dry mouth.
- Constipation.
- Sleep problems.
See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)
What To Think About
Sibutramine is approved by the U.S. Food and Drug Administration (FDA) for use for longer than 1 year. But its safety and effectiveness after 2 years of use have not been widely studied.
Because sibutramine can raise blood pressure, people who take it should have regular blood pressure checks. People with uncontrolled high blood pressure should not take sibutramine. But weight loss often lowers blood pressure, so it is possible that any increase in blood pressure caused by the medicines may be offset.
Along with this medicine, consider using a support program that helps you change your eating habits and lifestyle. Because behavior change (diet and exercise) is needed along with sibutramine use, a support program can improve your chances of successfully losing weight. The maker of sibutramine provides a free support program with your prescription. It is designed to help you create a weight-loss plan that fits your lifestyle.
After you stop taking sibutramine, you may regain some or all of the weight you lost while taking the medicine, unless you have made permanent changes in your eating and exercise habits.
Clinical trials of sibutramine have not detected an increase in heart or lung problems, which were seen with dexfenfluramine and fenfluramine (fen-phen). But these trials may not have been long enough or large enough to discover relatively rare or long-term problems with sibutramine.
When taking sibutramine, it is possible to develop "serotonin syndrome," a potentially deadly condition, if you also take dextromethorphan (found in cough syrups), ergot, sumatriptan succinate (found in migraine medicines), lithium, fentanyl, demerol, or certain types of antidepressants (selective serotonin reuptake inhibitors, or SSRIs). Some of the symptoms of serotonin syndrome include dizziness, euphoria, agitation, confusion, and shivering. Before taking sibutramine, make sure to tell your doctor about any other medicines you are taking.
Complete the new medication information form (PDF)
(What is a PDF document?) to help you understand this medication.
References
Citations
Wirth A, Krause J, (2001). Long-term weight loss with sibutramine: A randomized, clinical trial. JAMA, 286(11): 1331–1339.
Li Z, et al. (2005). Meta-analysis: Pharmacologic treatment of obesity. Annals of Internal Medicine, 142(7): 532–546.
Lean MEJ (1997). Sibutramine: A review of clinical efficacy. International Journal of Obesity, 21(Suppl 1): S30–S36.
Credits
| Author | Caroline Rea, RN, BS, MS |
| Editor | Susan Van Houten, RN, BSN, MBA |
| Associate Editor | Pat Truman, MATC |
| Primary Medical Reviewer | Caroline S. Rhoads, MD - Internal Medicine |
| Specialist Medical Reviewer | Matthew I. Kim, MD - Endocrinology & Metabolism |
| Last Updated | April 20, 2007 |
