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Medications for Obesity

The information provided here is meant to give you a general idea about each of the medications 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 medications as recommended by your doctor, or according to the instructions provided. If you have further questions about usage or side effects, contact your doctor.

Medications for obesity should not be used alone. Rather, they should be part of a comprehensive weight loss program that includes:

  • Reduced caloric intake
  • Regular exercise and other behavior changes
  • Psychological counseling (if needed)

Prescription Medications

Central Nervous System Medications

  • Lorcaserin
  • Phentermine
  • Phendimetrazine
  • Diethylpropion
  • Phentermine plus extended release topiramate

Fat Absorption Blockers

  • Orlistat (as prescription or over-the-counter)

Glucagon-Like Peptide-1 (GLP-1) Inhibitors

  • Liraglutide

Monoamine Oxidase Inhibitors (MAOI)

  • Naltrexone-Bupropion

Prescription Medications

Central Nervous System Medications

Medications approved for adults include:

  • Lorcaserin
  • Phentermine
  • Phendimetrazine
  • Diethylpropion
  • Phentermine plus extended release topiramate

Medications approved for children and adolescents include:

  • Amphetamine sulfate (for children over 11 years old)
  • Phentermine or diethylpropion (for children over 16 years old only)

These medications act on your brain to suppress your appetite. Lorcaserin is approved for long-term use. Phentermine, phendimetrazine and diethylpropion are only recommended for short-term use (a few weeks).

Possible side effects include:

  • Lightheadedness
  • Dry mouth
  • Headache
  • Constipation or diarrhea
  • Nausea
  • Nervousness
  • Sleeplessness
  • Restlessness
  • Elevated blood pressure
  • Heart problems

Also:

  • Lorcaserin
    • Fatigue
    • Back pain
    • Cough
  • Phentermine and amphetamine sulfate:
    • Difficulty urinating
    • Rash
  • Phentermine plus extended release topiramate
    • Numbness or tingling of skin
    • Change in taste
    • Depression
Fat Absorption Blockers

Orlistat:

  • Xenical (prescription)
  • Alli (over-the-counter)

Approved for use in children and adults over 11 years old. Taken at a dose of 120 milligrams (mg), 3 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 some, the fat is excreted by the body between bowel movements as an oily discharge. It is recommended for long-term use (up to about 2 years). Orlistat is also available in a 60 mg over-the-counter form, called Alli.

Possible side effects include:

  • Staining of underwear
  • Gas
  • Pressure to empty bowels
  • Leakage of stool
  • Increased frequency of bowel movements
  • Severe liver damage (rarely)
Glucagon-Like Peptide-1 (GLP-1) Inhibitors
  • Liraglutide

Liraglutide is used for chronic weight management if you have at least one other weight-related complication. It works by making you feel less hungry or fuller faster while eating. The medication is given as a daily injection. Dosage is slowly increased until you are up to 3 mg a day.

Possible side effects may include:

  • Nausea
  • Constipation
  • Diarrhea
  • Abdominal pain
  • Headache
  • Increased heart rate
  • Serious side effects may include an increased risk of pancreatitis.
Monoamine Oxidase Inhibitors (MAOI)
  • Naltrexone-Bupropion

Used for chronic weight management in combination with a reduce calorie diet and regular exercise. The pill is a combination of 2 drugs. It works by making you feel less hungry or fuller faster while eating. The medication is extended release tablet taken by mouth. Dosage is slowly increased from one table to 2 tablets a day.

This medication is not recommended in those with a history of poorly controlled high blood pressure, or a history of seizures, eating disorders (anorexia or bulimia), opioid dependency, or alcohol and drug withdrawal. If you are already taking bupropion for other reasons, do not take this medication.

Possible side effects include:

  • Lightheadedness
  • Constipation
  • Diarrhea
  • Nausea or vomiting
  • Dry mouth
  • Sleeplessness
  • Increased heart rate
  • Elevated blood pressure
  • Serious side effects may include liver damage

NOTE: This medication may increase the risk of suicidal thoughts or actions. If you have these thoughts or actions, call for emergency medical services right away.

Over-the-Counter (OTC) Medications

OTC medications advertised as promoting weight loss, except for Alli, 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.

Special Considerations

If you are taking medications, follow these general guidelines:

  • Take the medication as directed. Do not change the amount or the schedule.
  • Ask what side effects could occur. Report them to your doctor.
  • Talk to your doctor before you stop taking any prescription medication.
  • Do not share your prescription medication.
  • Medications can be dangerous when mixed. Talk to your doctor or pharmacist if you are taking more than one medication, including over-the-counter products and supplements.
  • Plan ahead for refills as needed.

Revision Information

  • Meridia (sibutramine): market withdrawal due to risk of serious cardiovascular events. US Food & Drug Administration website. Available at: https://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm228830.htm. Updated September 9, 2013. Accessed February 23, 2017.

  • Meridia (sibutramine hydrochloride): follow-up to an early communication about an ongoing safety review. US Food & Drug Administration website. Available at: https://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm198221.htm. Updated September 9, 2013. Accessed February 23, 2017.

  • Obesity. Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/nutritional-disorders/obesity-and-the-metabolic-syndrome/obesity. Update December 2016. Accessed February 23, 2017.

  • Orlistat (marketed as Alli and Xenical): labeling change. US Food & Drug Administration website. Available at: https://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm213448.htm. Updated September 6, 2013. Accessed February 23, 2017.

  • Pai You Guo, marketed as dietary supplement—recall. US Food & Drug Administration website. Available at: https://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm190531.htm. Updated August 29, 2013. Accessed February 23, 2017.

  • Prescription medications for the treatment of obesity. National Institute of Diabetes and Digestive and Kidney Diseases. Available at: https://www.niddk.nih.gov/health-information/health-topics/weight-control/prescription-medications-treat-overweight-obesity/pages/facts.aspx. Updated July 2016. Accessed August February 23, 2017.

  • Weight loss medications for obesity in adults. EBSCO DynaMed website. Available at: http://www.dynamed.com/topics/dmp~AN~T361156/Weight-loss-medications-for-obesity-in-adults. Updated May 27, 2016. Accessed February 23, 2017.

  • Weight loss medications for obesity in children and adolescents. EBSCO DynaMed website. Available at: http://www.dynamed.com/topics/dmp~AN~T474269/Weight-loss-medications-for-obesity-in-children-and-adolescents. Updated January 27, 2016. Accessed February 23, 2017.

  • 9/17/2010 DynaMed Plus Systematic Literature Surveillance http://www.dynamed.com/topics/dmp~AN~T116362/Weight-loss-medications-withdrawn-from-market: James WP, Caterson ID, Coutinho W, et al. Effect of sibutramine on cardiovascular outcomes in overweight and obese subjects. N Engl J Med. 2010;363(10):905-917.