U.S. Food and Drug Administration

 FDA Talk Paper,   Jan 21, 1999

FDA WARNS ABOUT PRODUCTS CONTAINING GAMMA BUTYROLACTONE OR GBL AND ASKS COMPANIES TO ISSUE A RECALL

The Food and Drug Administration is alerting consumers not to purchase or consume products, some of which are labeled as dietary supplements, that contain gamma butyrolactone (abbreviated as GBL). FDA has also asked the companies that manufacture these products to voluntarily recall them. The agency has received reports of serious health problems -- some that are potentially life-threatening -- associated with the use of these products.

Although labeled as dietary supplements, these products are illegally marketed unapproved new drugs. Products containing GBL are marketed under various brand names including Renewtrient, Revivarant or Revivarant G, Blue Nitro or Blue Nitro Vitality, GH Revitalizer, Gamma G, and Remforce. They are promoted with claims to build muscles, improve physical performance, enhance sex, reduce stress and induce sleep.

GBL is also known by the chemical names 2(3H)-furanone dihydro; butyrolactone; gamma-butyrolactone; 4-butyrolactone; dihydro-2(3H)-furanone; 4-butanolide; 2(3H)-furanone, dihydro; tetrahydro-2-furanone; and butyrolactone gamma.

GBL related products have been associated with reports of at least 55 adverse health effects, including one death. In 19 of those cases, the consumers became unconscious or comatose and several required intubation for assisted breathing. Other reported effects included seizures, vomiting, slow breathing, and slow heart rate. There are reports of at least 5 children under 18 years of age who have been injured or who have suffered these kinds of effects.

When taken orally, GBL is converted in the body to gamma hydroxybutyrate or GHB. GHB is a very potent unapproved drug. It is currently being investigated under the supervision of doctors for the treatment of narcolepsy. Because of its serious side effects, GHB should not be taken unless in the context of these FDA approved investigations. FDA and the Justice Department have ongoing criminal enforcement actions against GHB. GBL should not be taken.

Products containing GBL are sold in liquid and powder form. They are sold via the Internet, in some health food stores, and in some gymnasiums and fitness centers.

Consumers are advised to dispose of any products of this type in their possession. If they have experienced adverse health problems from use of these products, they should promptly contact a physician. FDA requests consumers and physicians to report adverse events to FDA's MEDWATCH 1-800-332-1088.

The Trimfast Group, Inc. has agreed to recall the product Revivarant, 32 ounces of liquid in a plastic bottle, and Revivarant G, 200 grams of powder in a pill bottle. Other companies manufacturing products containing GBL are being asked by the FDA to voluntarily recall them.

FDA is considering all potential regulatory actions at its disposal if products containing GBL are not recalled. The agency will act expeditiously to protect the public health.

The text in this article was prepared by the FDA Office of Public Affairs.