Weight Loss Drugs Linked to Liver, Kidney, and Pancreas Damage
By Denise Mann
WebMD Health News
Latest Medications News
Reviewed by Laura J. Martin, MD
April 15, 2011 -- The consumer advocacy group Public Citizen is urging the FDA to immediately pull two weight loss drugs, Xenical and Alli, from the market. The group says the drugs' risk for liver, pancreas, and kidney damage greatly outweighs any potential weight loss benefits.
Xenical and Alli are different strengths of the drug orlistat. Prescription-strength Xenical is manufactured by Roche. Alli is available over the counter, and is one-half the strength of Xenical. These drugs block the absorption of fat in the gastrointestinal tract. Alli manufacturer GlaxoSmithKline announced plans to sell the rights to the over-the-counter drug Alli.
In May 2010, the FDA issued a warning based on post-marketing adverse events about risk of severe liver injury in people taking orlistat, citing 12 foreign reports of liver toxicity with Xenical and one case of liver toxicity in the U.S. associated with the use of Alli. Two of these patients died, and three needed liver transplants as a result of this damage.
Washington-D.C. based Public Citizen has now identified 73 cases of kidney stones linked to use of these drugs, 23 of which required hospitalization, along with 47 cases of acute pancreatitis from the FDA adverse event reports. This is Public Citizen's second petition to have Xenical removed from the market. Their first petition was rejected. The FDA will now mull the new petition.
If you are taking these drugs, don't wait for the FDA to act, says Public Citizen director Sidney Wolfe, MD.
"Stop taking them," he says. "Unlike other drugs, which have a withdrawal syndrome that you would go through if you suddenly stop, there is no downside to stopping Xenical or Alli.
"The risks greatly outweigh the benefits," he says. "The drug doesn't add all that much to weight loss efforts. This has got to be the end of the drug. How much more danger do you need for a drug that doesn't work very well?"
According to Public Citizen, the average additional weight loss after one year among people taking orlistat while dieting and exercising compared to those who just did diet and exercise was 5.6 additional pounds with the 60 mg dose and 7 additional pounds with the 120 mg dose. The drugs are also known to cause other mild side effects, including inability to control bowel movements, oily or fatty stools, and oily spotting.
"Patient safety is of the utmost importance to Roche, and we regularly monitor the safety profile of all our medicines and provide this information to the FDA," Roche spokesman Christopher Vancheri says in a written response. "Roche has not yet had the opportunity to thoroughly review the Public Citizen petition and therefore, cannot make any further comments."
He adds that "the efficacy and safety profile of Xenical is based on more than 10 years of clinical experience, and more than 38.7 million patients worldwide have received Xenical since it was first introduced to the market in 1998. The efficacy and safety of orlistat is based on more than 14,000 patients assessed in clinical studies."
Deborah G. Bolding, communications manager-North America for GlaxoSmithKline, says "GlaxoSmithKline (GSK) is committed to ensuring that consumers and physicians understand the safety profile of orlistat and Alli.
"Alli is safe and effective when used as directed," Bolding says. "Orlistat is minimally absorbed in the blood and works locally in the gastrointestinal tract. GSK continues to proactively monitor for the safety of orlistat and share all relevant information with regulatory agencies."
People using Alli should talk to their doctors or pharmacist if they have any concerns.
Jury Still Out on the Safety and Efficacy of Alli, Xenical
Louis Aronne, MD, founder and director of the Comprehensive Weight Control Program at New York-Presbyterian Hospital/Weill Cornell Medical Center in New York City, is reserving his judgment on the benefits and risk of these drugs.
"Based on the large numbers of people who have taken these drugs, the chance seems very small of having any kind of complication," Aronne says. "There is a benefit if someone is losing weight and maintaining that loss on these medications."
His advice is to get evaluated by your physician if you are taking these drugs and have concerns about your risk of side effects.
Jeff Stier, a senior fellow at the Washington, D.C.-based National Center for Public Policy Research, follows health and science issues and agrees that the number of incidents reported compared to the overall number of doses taken over many years is "extremely low."
This medicine is not a magic bullet for obesity, he says. "It only works in conjunction with proper diet and exercise, but it can give people the boost they need to achieve healthy goals."
SOURCES: Louis Aronne, MD, founder and director, Comprehensive Weight Control Program, New York-Presbyterian Hospital/Weill Cornell Medical Center, New York City.Sidney Wolfe, MD, Public Citizen director, Washington, D.C.Public Citizen petition to FDA, April 14, 2011.Jeff Stier, senior fellow, National Center for Public Policy Research, Washington, D.C.Christopher Vancheri, director of public affairs, Genentech Inc., a member of the Roche Group, Nutley, N.J.Deborah G. Bolding, communications manager-North America, GlaxoSmithKline Consumer Healthcare.
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