Does Ozempic Cause Hair Loss?

Marlene Busko


May 25, 2023

Should people be concerned about possible hair loss when taking Wegovy, Ozempic, or Mounjaro for weight loss (where the latter two drugs are being used off label) — as was recently claimed by some people on social media and reported in news stories?

The consensus among dermatologists and endocrinologists contacted by Medscape is no.

It's up to the individual to weigh the benefits of treating obesity against the risks of the therapy, including the low risk of developing temporary hair loss, says one expert.

Wegovy, Ozempic, and Mounjaro

Of these three newer medications, only the glucagon-like peptide-1 (GLP-1) receptor agonist semaglutide (Wegovy) is approved by the US Food and Drug Administration (since June 2021) for weight management — specifically for people with either obesity (body mass index [BMI] ≥ 30) or overweight (BMI ≥ 27) plus at least one weight-related comorbidity such as hypertension, type 2 diabetes, and high cholesterol — with a dosage up to a 2.4-mg weekly injection.

When there was a short supply of Wegovy soon after it became available, some people turned to the same drug — semaglutide, but marketed as Ozempic for type 2 diabetes, which is titrated up to a 2-mg weekly injection. Still others opted for tirzepatide (Mounjaro), a dual GLP-1 agonist and glucose-dependent insulinotropic polypeptide (GIP) agonist. Tirzepatide is approved for type 2 diabetes in the US but is not yet approved for weight loss.

Wegovy shortages continue to be reported.

Alopecia (hair loss) was an uncommon side effect in the clinical trials of these medications; of interest, it was more common after bariatric surgery.

In clinical trials, 3% of patients receiving Wegovy (a 2.4-mg/wk injection) vs 1% of patients receiving placebo reported alopecia. Hair loss was not reported as a side effect in clinical trials of Ozempic (a 2-mg/wk injection) for type 2 diabetes. In a clinical trial of tirzepatide for weight loss in obesity, 5.7% of patients taking the highest dose (a 15-mg once-weekly injection) reported alopecia vs 1% of those who got a placebo.

In contrast, a review of 18 mostly observational studies reported that 57% of patients had hair loss after bariatric surgery.

Is It the Drug or the Rapid Weight Loss?

None of the experts consulted by Medscape had seen patients who came to them about hair loss while taking these drugs for weight loss.

"I have not seen patients complaining of hair loss from these medications, but perhaps it is just a matter of time," said Lynne J. Goldberg, MD, a professor of dermatology and pathology and laboratory medicine, at Boston University School of Medicine, and director of the hair clinic at Boston Medical Center.

"Some of my patients lose hair when they lose weight, generally as a result of the weight loss itself and not as a side effect of these medications," said Katharine H. Saunders, MD, an obesity medicine physician, co-founder of Intellihealth, and an assistant professor of Medicine at Weill Cornell Medicine in New York City.

"Hair loss from rapid weight loss is very common [and] not necessarily a side effect of the medication itself but more as a result of how quickly the weight loss occurs," echoed Susan Massick, MD, associate professor of dermatology, Ohio State University, and a dermatologist at Ohio State's Wexner Medical Center.

"Hair loss is tricky," Anne Peters, MD, observed. "Losing weight and/or changing your diet causes hair loss. Stress can cause hair loss," said Peters, director of the USC Clinical Diabetes Programs in Los Angeles. "So, it is hard to separate weight loss from medication effect," she said.

Telogen Effluvium (Stress Shedding) With Rapid Weight Loss

The hair loss seems to be associated with rapid weight loss, the experts agree.

"It is rare, but we can see patients who have a period of diffuse hair loss, called telogen effluvium, or 'stress shedding' with rapid weight loss," said Michael A. Weintraub, MD, an endocrinologist at NYU Langone Health in New York City.

This hair loss occurs in relation to either physical (surgery, pregnancy, illness) or emotional stress, added Weintraub, who is an assistant professor at NYU Grossman School of Medicine.

Hair loss due to rapid weight loss could be caused by an antiobesity medication, but it could also occur with other obesity treatments, such as bariatric surgery or drastic dietary changes, he said. The hair shedding is typically short-lived and reversible.

About 80%-85% of hair is in the anagen (growth) phase, about 5% is in a transitional (catagen) phase, and the rest is in telogen (resting, or shedding) phase, Massick explained. In telogen effluvium, hairs that are normally in the growth phase get suddenly shifted to telogen phase and are shed rapidly.

"Telogen effluvium can be caused by rapid weight loss, major surgery, severe COVID infection, high fever, or death in the family," she noted. "You will not go bald with telogen effluvium, but you might find that you may lose a good volume of hair," much more than the normal loss of up to 100 hairs a day.

"I counsel my patients about the possibility of losing hair before they undergo bariatric surgery," Saunders said. "Generally, the health benefits of weight loss and weight maintenance outweigh the risk of temporary hair loss."

Nutritional deficiencies and malnutrition can contribute to hair loss as well, and iron deficiency is sometimes a culprit, she added.

"If someone is worried" about hair loss associated with weight loss, "they should see their doctor," Peters said. "If they are on thyroid hormone, in particular, the levels should be retested after weight loss."

Hair loss appears more common after bariatric surgery than with antiobesity medications," Weintraub observed, and it is unclear whether this is because the weight loss is more dramatic after surgery and thus a greater stressor, or whether it is due to nutrient deficiency or a different mechanism entirely.

"Unlike certain forms of bariatric surgery, which can lead to malabsorption (eg, Roux-en-Y gastric bypass), medications such as GLP-1 agonists and GLP-1/GIP dual agonists do not cause malabsorption," Weintraub noted. "So nutritional deficiencies are less likely to be the cause of new hair loss in those taking antiobesity medications than [in] someone who underwent bariatric surgery."

Iron and vitamin D deficiencies are the most common nutritional deficiencies that can cause hair loss, he noted.

Slow and Steady Weight Loss Rather Than Rapid

"I would suggest that patients try to keep the weight loss slow and steady, rather than rapid," Goldberg said, "and follow any vitamin/mineral supplementation plan that they are given. Patients with bariatric surgery have nutritional guidance and a supplementation plan."

"Follow a well-balanced dietary strategy with ample protein, vegetables, and some fruit," Saunders advises. Healthcare providers should monitor lab tests to check for and treat vitamin deficiencies, and registered dietitians can be crucial to ensure proper nutrition. She advises patients: "Find coping strategies to reduce stress and get enough sleep. If iron levels are low, start an iron supplement under your provider's supervision."

"Some of my patients swear by biotin supplements, prenatal vitamins or 'hair, skin, and nails' vitamins," she added. If hair loss doesn't stop, a dermatologist can look for other contributors and discuss strategies for hair restoration.

Individuals who undergo bariatric surgery require lifelong vitamin supplementation and yearly (or more frequent) lab testing, she noted.

"With, for example, bariatric surgery or any type of diet change you want to make sure you still maintain a balanced diet, whether its calories, protein, iron, zinc, vitamins (vitamin D for example)," Massick echoed.

Similarly, Peters advises: "I would say to maintain a normal healthy diet even if eating less. Exercise. Do all those healthy things. Taking a daily multivitamin isn't a bad idea. Talk with a nutritionist. Use the appetite suppression of the medication to combine with healthy eating."

"If someone is having new hair loss, they should see their clinician to evaluate for all possible causes," Weintraub said. "Their provider can evaluate for underlying causes like thyroid dysfunction, iron deficiency, and vitamin D deficiency."

However, if a patient's pattern of hair loss is not diffuse but occurs in patches, this has an entirely different set of etiologies probably unrelated to antiobesity medication and should be evaluated.

Working with a nutritionist to ensure that patients have sufficient protein and micronutrient intake can lower the risk of developing hair loss and other complications, Weintraub said. "This is particularly important for certain forms of bariatric surgery such as Roux-en-Y gastric bypass, since that can lead to malabsorption of specific vitamins and minerals that need to be periodically measured and supplemented."

In individuals starting an antiobesity medication, beginning a daily multivitamin has little harm, he added, and can ensure they are getting essential minerals and vitamins. However, no studies have specifically investigated this yet.

"Ultimately, it's important to weigh the benefits of antiobesity medications against the potential risks, as we do with any medical intervention," according to Weintraub.

"The purpose of treating obesity," he stressed, "is to reduce the risk of heart disease, stroke, and multiple types of cancers. It's up to the individual to weigh these benefits against the risks of the treatment, including the low risk of developing temporary hair loss."

Peters writes a column for Medscape and discloses that she served as a consultant for Blue Circle Health, Vertex, and Abbott Diabetes Care, received a research grant from Abbott Diabetes Care, and received stock options from Teladoc and Omada Health. Goldberg, Saunders, Massick, and Weintraub declared no relevant financial relationships.

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