Prescription Drugs and Dietary Supplements for Weight Loss

Abstract

Despite much advertising to the contrary, there are no dietary supplements that safely and effectively cause weight loss. Moreover, some of them are adulterated with banned prescription drugs as well as narcotics, stimulants, antidepressants, anorectics, laxatives and diuretics. There are several analytical methods, including LC-MS/MS and NMR that can be used to analyze dietary supplements for adulterants. Such methods can be used to detect and quantify them at physiologically relevant concentrations of >1%. Even though many supplements don’t contain any of these potentially deadly adulterants, many do contain caffeine and/or green tea extract at such high concentrations that they can also be quite toxic. On the other hand, there are five prescription drugs that are FDA-approved as an adjunct to counseling, diet and exercise for maintaining weight loss. They are orlistat (Xenical® or Alli when sold over-the-counter), lorcaserin (BELVIQ®), phentermine plus extended-release topiramate (Qsymia®), naltrexone plus bupropion (Contrave®) and liraglutide (Saxenda®). Unlike dietary supplements, they were all developed in research programs that were conducted through good laboratory practices (GLP) and manufactured by current good manufacturing practices (cGMP). So, they have been shown to be safe and effective. Moreover, every step in the manufacturing process is monitored and documented to ensure the purity of the drugs. Finally, post-market monitoring of potential adverse side effects is done on these drugs.