Wegovy is linked to an increased risk of hair loss, study suggests

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Yet another study is zeroing in on the unintended side effects of Novo Nordisk‘s semaglutide – the active ingredient in the company’s blockbuster weight loss drug Wegovy and diabetes treatment Ozempic. 

But this time, the study highlights the risk of hair loss. 

To be clear, semaglutide’s link to hair loss isn’t new. Clinical trials conducted by Novo Nordisk have shown a higher risk of hair loss in patients who took semaglutide compared to those who took a placebo. 

Wegovy and Ozempic are part of a class of popular medications called GLP-1s, which mimic a hormone in the gut to suppress appetite and regulate blood sugar. Those drugs are known for their gastrointestinal side effects such as nausea and vomiting, and have also faced increased scrutiny after some patients reported experiencing stomach paralysis and suicidal ideation while taking them. 

In a statement, Novo Nordisk said it “remains confident in the benefit-risk profile of our GLP-1 medicines, when used consistent with their indications and product labeling.”

The new study, conducted by researchers at the University of British Columbia and not yet submitted for peer review, shows that semaglutide is associated with hair loss compared to users of an older weight loss pill called Contrave, or bupropion-naltrexone. 

The researchers examined data from 16 million patients from 2006 to 2020 and identified 1,926 semaglutide users and 1,348 Contrave users. People with a diagnosis of diabetes or who used antihyperglycemics – medications that lower blood sugar levels – were excluded. 

The incidence rates of hair loss were higher among semaglutide users than Contrave users. Overall, patients who took semaglutide had a 52% higher risk of hair loss compared to those who took Contrave. 

The researchers also found that women who took semaglutide had more than two times the risk of hair loss compared to women in the Contrave group. But Mohit Sodhi, one of the authors, told CNBC that “most of our data was driven by women” so they cannot compare men versus women in the study. 

Among those who took semaglutide, there were 22 cases of hair loss in women and just one case in men. Future studies with larger sample sizes of patients are needed to determine if there is a difference between men and women, Sodhi noted. 

The researchers also did not follow patients if they stopped semaglutide or Contrave, so it is unclear whether the risk of hair loss decreases once they are off Novo Nordisk’s drug, according to Sodhi. More research is required in that area, he said. 

So, why might semaglutide cause a higher risk of hair loss? 

One factor could be the physiological stress that rapid weight loss can induce, which can lead to the “disruption of the natural hair cycle,” according to Sodhi. He said that may be a more prominent effect of semaglutide because it is known to decrease weight more rapidly than Contrave. 

Semaglutide’s ability to suppress appetite also leads to patients consuming less food, which can potentially cause nutrient deficiencies, including protein in particular, Sodhi added. Protein deficiencies have been shown to be linked to hair loss, he noted. 

Sodhi said patients may also lose nutrients through vomiting when on semaglutide. Some health experts also hypothesize that semaglutide can lead to hormonal shifts that increase the risk of a common form of hair loss called androgenic alopecia, he added. 

People, and women in particular, considering using semaglutide strictly for weight loss may want to “factor in hair loss as a possible limitation” of the drug, the researchers said in the study. But people with diabetes or morbid obesity may weigh their risks and benefits differently, and may be more willing to accept hair loss as a potential risk, the researchers added. 

One of the study authors, Dr. Mahyar Etminan, has previously consulted on litigation related to Ozempic. 

Feel free to send any tips, suggestions, story ideas and data to Annika at annikakim.constantino@nbcuni.com.

Dexcom received a warning letter from the U.S. Food and Drug Administration last week after the agency inspected the company’s manufacturing facilities in San Diego, California, and Mesa, Arizona.

The FDA “observed non-conformities” with Dexcom’s quality management system and manufacturing processes, according to a Friday company filing with the U.S. Securities and Exchange Commission. The agency also noted that the company’s response to its list of observations, formally known as Form 483, was insufficient. 

“The Company takes the matters identified in the warning letter seriously, has already submitted several responses to the Form 483 and is in the process of preparing a written response to the warning letter,” Dexcom said in the filing. 

It was unclear what specific problems the FDA identified at the facilities. 

Dexcom produces devices called continuous glucose monitors that can help users track their blood sugar and manage diabetes. The FDA’s warning letter does not limit Dexcom’s ability to manufacture or distribute its products.

The company did not immediately respond to CNBC’s request for comment. 

Dexcom also appointed Renée Galá, chief operating officer of Jazz Pharmaceuticals, to its board of directors last week. Galá has worked in her current role since 2023, and she previously served as the chief financial officer at Jazz.

She has also held leadership roles at Grail and Theravance Biopharma, and she spent several years at the pharmaceutical giant Eli Lilly. 

“Renée’s extensive experience guiding global finance and global operations including commercial and R&D to drive growth and create shareholder value provides an excellent fit at this key point in Dexcom’s journey,” Dexcom CEO Kevin Sayer said in a release. 

As of intraday trading on Tuesday morning, shares of Dexcom are down about 9% year to date. 

Read the full release here.

Feel free to send any tips, suggestions, story ideas and data to Ashley at ashley.capoot@nbcuni.com.