U.S. NIH’s Obesity Guidelines Part 30: Diet drugs for weight loss

Phenylpropanolamine (PPA). Phenylpropanolamine (PPA), available over-the-counter, has been shown to be effective for up to one year. Average weight loss is 3.3 pounds greater with PPA than with a placebo after two months (5.7 pounds versus 2.4 pounds, respectively). (p. 53)

Note: PPA was removed from the market in 2000 because of the Yale Hemorrhagic Stroke Study which concluded that PPA diet pills increase the risk of hemorrhagic stroke. I disagree with the results of this study.

Meridia (sibutramine) causes an average weight loss of 6.2 lbs more than placebo

Average weight loss is 6.2 pounds greater with Meridia than with a placebo after one year (9.7 pounds versus 3.5 pounds, respectively). (p. 54)

Meridia (sibutramine) should not be taken if you have a history of heart disease or stroke

Anyone with a history of coronary heart disease, congestive heart failure, arrhythmias, or history of stroke should not take Meridia. (p. 84)

People taking Meridia (sibutramine) should monitor their blood pressure

All patients should have their blood pressure monitored while taking Meridia (sibutramine).

Redux (dexfenfluramine) causes an average weight loss of 5.7 lbs more than placebo

Average weight loss is 5.7 pounds greater with Redux (dexfenfluramine) than with a placebo after one year (21.6 pounds versus 15.9 pounds, respectively). (p. 54)

Note: Redux (dexfenfluramine) and Pondimin (fenfluramine) were removed from the market in 1997 because of an associated with heart valve damage.

Xenical (orlistat) causes an average weight loss of 4.9 lbs more than placebo

Average weight loss is 4.9 pounds greater with Xenical than with a placebo after four months (9.5 pounds versus 4.6 pounds, respectively). (p. 54)

Ephedrine and caffeine causes an average weight loss of 7.5 lbs more than placebo

Average weight loss with ephedrine and caffeine is 7.5 pounds greater than with a placebo after six months, however, this combination is not approved by the Food and Drug Administration (FDA) and therefore is not recommended. (p. 116)

Other weight loss drugs

The report also briefly mentioned the results of Weintraub’s Fen-Phen study, but other weight loss medicines were not reviewed because there were no recent studies (since 1980) that met their criteria for review. (p. 54)

Mazindol, phentermine, diethylpropion, and phendimetrazine are approved for short-term use only

The report notes that mazindol, phentermine, diethylpropion, and phendimetrazine are approved for short-term use only. (p. 84 and 116)

Drugs not approved for weight loss

It also states that ephedrine and caffeine, Prozac? (fluoxetine), cimetidine, mianserine, yohimbine, testosterone, femoxetine, and the beta-3 agonist BRL 26830A are not approved for weight loss. (p. 84 and 116)

Studies before 1980 not included

Their research was limited to papers cataloged in Medline between 1980 and 1997. (p. 101) Therefore earlier studies of older drugs such as phentermine, diethylpropion and phenylpropanolamine were not included.

Other therapies: Herbs, supplements, hypnotherapy, and acupuncture

Other therapies such as herbal remedies, nutritional supplements, hypnotherapy, and acupuncture did not meet the requirements for review by this committee. (p. 55)

Herbs not recommended for weight loss

The report states that:

“[H]erbal medications are not recommended as part of a weight loss program. These preparations have unpredictable amounts of active ingredients and unpredictable and potentially harmful effects.” (p. 86)

REFERENCE

Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults : the evidence report / National Heart, Lung, and Blood Institute [Bethesda, Md.] : National Institutes of Health, National Heart, Lung, and Blood Institute, [1998]. NIH publication No. 98-4083.

Articles on the same subject can be found here:

• Diet Pills (General Info)

• Diethylpropion (Tenuate)

• Meridia (sibutramine)

• Obesity Guidelines, NIH

• Phendimetrazine (Bontril)

• Phentermine

• Xenical (orlistat)