Study Raises New Questions Over Ozempic Hair Loss Risks

Researchers have identified biological mechanisms that may explain how GLP-1 drugs can trigger both hair loss and hair growth.

While evidence on whether side effects of Ozempic, Mounjaro and similar GLP-1 drugs cause hair loss remains inconclusive, researchers warn that rapid or significant weight loss can intensify the condition.

Ozempic (semaglutide) was approved as a treatment for type 2 diabetes in 2017 and is part of a new class of medications known as glucagon-like peptide-1 (GLP-1) receptor agonists. While it was introduced as a diabetes drug, amid aggressive advertisements that promoted the weight loss benefits, Ozempic has increasingly been prescribed as a diet drug in recent years, making it a blockbuster treatment that is now used by millions of Americans. 

This ultimately resulted in Novo Nordisk releasing a weight loss–specific version of the drug called Wegovy, while Eli Lilly developed Mounjaro (tirzepatide), Ozempic’s main competitor, along with its own weight loss counterpart, Zepbound.

Both companies face hundreds of Ozempic lawsuits, Mounjaro lawsuits and Wegovy lawsuits alleging that in a rush to reap profits from the drugs, manufacturers have failed to adequately research potential side effects or warn patients about serious risks associated with the medications, including stomach paralysis, bowel obstruction and a rare form of vision loss.

However, one of the earliest concerns with GLP-1 drugs, and Ozempic specifically, involved what appeared to be an association with alopecia, also known as hair loss. Researchers from Saudi Arabia have now published a study in the medical journal Cureus on September 16, indicating that there are signs that the drugs can cause hair loss in some situations, yet may help with hair growth in others.

Led by Omar A. Alsuwailem, the research team conducted a systematic review of studies on GLP-1 drugs and hair loss, identifying five studies involving 2,905 adult patients treated with Ozempic, Wegovy, Mounjaro or Zepbound.

Some data, including studies on Mounjaro, suggest a potential benefit for hair growth, while other research on both Ozempic and Mounjaro indicates the drugs may more than double the risk of hair loss. No similar associations, positive or negative, were identified with other GLP-1 drugs, researchers reported.

In previous studies, the team found that researchers have presented theories about the mechanism of actions that explain how GLP-1 could do either.

“Although the proposed mechanism by which GLP-1 RAs cause alopecia is still not well established. Some studies describe it as rapid weight loss leading to malnutrition and essential vitamin deficiencies, which disrupts hair growth and triggers the development of alopecia.”

— Omar A. Alsuwailem, Hair Loss Associated with Glucagon-Like Peptide-1 (GLP-1) Receptor Agonist Use: A Systematic Review

The researchers concluded that their “conflicting findings” emphasize the need for further research into the link between GLP-1 drugs and alopecia. They also recommended adding a patient education statement to the drugs that recommend clinicians warn patients about the potential hair loss risks and should encourage the patients to report any signs of alopecia.

Ozempic Stomach Paralysis Lawsuits

The study comes as more than 2,600 GLP-1 lawsuits involving gastrointestinal injuries continue to move forward in the Eastern District of Pennsylvania, where they have been consolidated before U.S. District Judge Karen S. Marston for coordinated discovery and pretrial proceedings, as part of a multidistrict litigation (MDL).

Judge Marston has focused the early stages of the litigation on issues that are key to whether the lawsuits can move forward, including discovery and pretrial motions regarding general causation evidence over the link between Ozempic and gastric obstructions, gastroparesis and other injuries, as well as questions about whether the claims are preempted by federal law.

Once those issues are resolved, the judge is expected to direct the parties to select several representative Ozempic lawsuits for early bellwether test trials, which will help the parties gauge how juries are likely to respond to evidence and testimony that would be presented throughout the litigation.

While the outcomes of the bellwether trials are not binding on other claims, they could help the parties reach an Ozempic settlement agreement that would avoid the need for each individual case to be sent back to their originating districts for costly individual trials in the future.