FDA Issues Kidney Injury Warning for OTC Weight Loss Pill Alli (Orlistat)
核心洞察
The FDA has required updated labeling for Haleon's over-the-counter weight loss drug Alli to include warnings about potential acute kidney injury (搜索), a rare but potentially fatal side effect.
A safety review identified 12 cases of kidney complications linked to orlistat, prompting the agency to recommend that people with a history of kidney disease or kidney stones consult a doctor before use.
The labeling changes also instruct consumers to stop taking Alli and seek medical attention if they develop symptoms such as back or groin pain, painful urination, blood in urine, or reduced urination.
The U.S. Food and Drug Administration has issued new safety warnings for Alli (orlistat), the only over-the-counter weight loss medication currently available in the United States, cautioning that the drug may cause acute kidney injury (搜索) in rare cases. The agency has approved updated labeling that highlights potential kidney problems, expanding upon existing precautionary language related to kidney stones.
The FDA's safety review identified 12 cases of kidney complications linked to the drug, prompting the agency to recommend that individuals with a history of kidney disease or kidney stones consult a healthcare professional before taking Alli.
"The labeling changes also tell consumers to stop using Alli and ask a doctor if they develop symptoms of kidney injury or kidney stones, such as back or groin pain, painful urination, blood in the urine, feet and leg swelling or less frequent urination," the FDA stated.
Scope of Use and Risk Profile
An estimated 40 million people have taken orlistat—available as the over-the-counter Alli or the higher-dose prescription version Xenical—since Xenical was first approved by the FDA in 1999. Alli, the 60-milligram lower-dose version, received FDA approval in 2007 and remains the first and only over-the-counter weight loss drug in U.S. history.
The risk to kidney health exists for both prescription and nonprescription doses, according to the agency. While the risk is rare and mild cases of acute kidney injury (搜索) may be reversible, untreated cases can be fatal. Between 2018 and 2023, 569,877 deaths were related to acute kidney injury in the United States, researchers reported last year.
Company Response
Haleon, which was spun off from GSK's consumer healthcare business in 2022, addressed the labeling update in a statement to The Independent. "The FDA recently required updates to harmonize labeling for all FDA-approved Orlistat medicines, including over-the-counter alli and higher-strength prescription versions. Alli labeling has always included a precautionary statement related to use by consumers with kidney stones," a Haleon spokesperson said.
"The newly-required updates expand the existing warning to include kidney disease, and provide additional detail to help consumers identify the signs and symptoms of potential kidney injury, a rare side effect for those who took Orlistat over-the-counter or prescription medicines," the spokesperson added, noting that the updates "reflect Haleon's ongoing commitment to transparency, patient safety and alignment with regulatory guidance."
Mechanism of Action and Historical Context
Alli's active ingredient, orlistat, works by blocking the digestive tract enzyme lipase, reducing the amount of dietary fat absorbed in the intestines by approximately one-quarter. The medication can be taken up to three times daily and is indicated for weight loss in adults when used in conjunction with a reduced-calorie diet. The prescription-strength version, Xenical, is indicated for obesity (搜索) management including weight loss, weight maintenance, and reducing the risk of weight regain after prior weight loss.
This is not the first time Alli has undergone safety review. In 2010, the FDA published a safety review following rare reports of serious liver injury, though the review found no evidence confirming orlistat as the cause. Additionally, counterfeit versions of Alli containing sibutramine—a compound linked to increased risk of heart attack and stroke—have previously been identified.
Expert Caution and Broader Context
Medical experts have raised concerns about taking Alli without healthcare professional supervision, citing risks of drug interactions, vitamin deficiencies, gastrointestinal side effects, and serious liver, kidney, and gallbladder complications, as well as potential misuse by individuals with eating disorders.
"These drugs have the potential to cause significant damage to multiple critical organs, yet they provide meager benefits in reducing weight loss in obese and overweight patients," Dr. Sidney Wolfe, former director of Public Citizen's Health Research Group, told ABC News.
The warning arrives amid a transformed weight-loss treatment landscape dominated by GLP-1 receptor agonists such as semaglutide (Ozempic, Wegovy) and tirzepatide (Zepbound), which work by suppressing appetite rather than blocking fat absorption. New oral GLP-1 formulations, including Eli Lilly's Foundayo and Novo Nordisk's Wegovy pill, have recently become widely available, offering once-daily alternatives to injectable therapies.