The information provided here is meant to give you a general idea about each of the medicines listed below. Only the most general side effects are included, so ask your doctor if you need to take any special precautions. Use each of these medicines as recommended by your doctor, or according to the instructions provided. If you have further questions about usage or side effects, contact your doctor.
Medicines for obesity should not be used alone. Rather, they should be part of a a comprehensive weight loss program that includes:
These medicines act on your brain to suppress your appetite. Phentermine and diethylpropion are only recommended for short-term use (up to about 12 weeks). Used alone, phentermine does not seem to produce the heart damage caused by its combination with fenfluramine (Phen-Fen), which was withdrawn from the US market.
Sibutramine is recommended for long-term use, up to about two years. If you have heart disease, uncontrolled high blood pressure, or other related conditions, sibutramine is not recommended.
Taken at a dose of 120 milligrams three times a day, Xenical prevents ingested fat from being absorbed by blocking digestive enzymes. About 30% of the fat you eat will remain in your bowels. In as many as 25% of people taking the drug, the fat is excreted by the body between bowel movements as an oily discharge.
It is recommended for long-term use (up to about two years). Orlistat is also available in a 60-mg over-the-counter form, called Alli.
Possible side effects include:
Staining of underwear
Pressure to empty bowels
Leakage of stool
Increased frequency of bowel movements
Severe liver damage (rare side effect)
Over-the-Counter (OTC) Medications
OTC medicines advertised as promoting weight loss are generally considered ineffective.
Some have led to serious side effects. Do not use over-the-counter or herbal remedies without talking to your doctor.
To view the latest product safety warnings and recalls, visit the Food and Drug Administration's
If you are taking medicines, follow these general guidelines:
Take your medicine as directed. Do not change the amount or the schedule.
Do not stop taking them without talking to your doctor.
Do not share them.
Use a measuring spoon, cup, or syringe to give the right dose. Make sure it has the same measurements as the medicine. For example, if the medicine is given in milligrams (mg), the device should also say mg.
Know what the results and side effects. Report them to your doctor.
Some drugs can be dangerous when mixed. Talk to a doctor or pharmacist if you are taking more than one drug. This includes over-the-counter medicine and herb or dietary supplements.
Arterburn DE, Crane PK, Veenstra DI. The efficacy and safety of sibutramine for weight loss: a systematic review.
Arch Intern Med.
Facts and comparisons.
Drug Facts and Comparisons
. 56th ed. St. Louis, MO: Facts and Comparisons; 2001.
Haddock CK, Poston WSW, Dill PL, Foreyt JP, Ericsson M. Pharmacotherapy for obesity: a quantitative analysis of four decades of published randomized clinical trials.
Int J Obes Relat Meta Disord.
Li Z, Maglione M, Mojica W, Arterburn D, et al. Meta-analysis: Pharmacologic treatment of obesity.
Ann Intern Med.
The Merck Manual of Diagnosis and Therapy
. 17th ed. Merck & Co; 1999.
Snow V, Barry P, Fitteman N, Qaseem A, et al. Pharmacologic and surgical management of obesity in primary care: a clinical practice guidelin from the American College of Physicians.
Ann Intern Med.
Wirth A, Krause J. Long-term weight loss with sibutramine: A randomized controlled trial.
Please be aware that this information is provided to supplement the care
provided by your physician. It is neither intended nor implied to be a
substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER
IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the
advice of your physician or other qualified health provider prior to
starting any new treatment or with any questions you may have regarding a