Could Wegovy Cause Hair Loss? (2025)

People who use Wegovy for weight management may be at higher risk for hair loss, according to a preprint study.

Researchers found that people prescribed semaglutide, the active ingredient in Wegovy, were 50% more likely to be diagnosed with a hair-loss condition compared to those taking another weight management drug called Contrave (bupropion-naltrexone).

Women had twice the risk of receiving a hair-loss diagnosis as men.

“Hair loss significantly affects quality of life,” said Mohit Sodhi, MD, resident emergency physician at the University of British Columbia and the first author of this study. “People should know about these potential effects so they can weigh out whether they are willing to accept the risk of side effects before starting the medication.”

In Wegovy clinical trials, 3.3% of people on the drug reported hair loss compared to 1.4% on placebo. Losing more weight increased the risk of hair loss.

Last year, the Food and Drug Administration (FDA) said it was investigating reports of hair loss, aspiration, and suicidal thoughts in people taking GLP-1 drugs. The agency has not provided an update on hair loss.

What Does the Study Show?

The study analyzed data from about 1,900 people taking semaglutide and 1,350 people taking Contrave, a weight loss medication that works differently from GLP-1 drugs. Researchers accounted for conditions linked to hair loss, including polycystic ovary syndrome (PCOS), depression, steroid use, and thyroid disease.

They found 22 cases of hair loss among women and one among men, though the study population included significantly more women overall.

“In order to understand this fully, we need replication from other similar studies, perhaps using larger databases, as well as possibly basic science studies to address the potential complication of GLP-1 agonist-induced hair loss,” Sodhi said.

This was a retrospective cohort study, meaning the researchers looked at outcomes after people had already taken the drugs for a while. The findings suggest semaglutide may increase the risk of hair loss, but they don’t establish a direct cause.

Why Might Wegovy Cause Hair Loss?

There are a few theories about how GLP-1 drugs like semaglutide may affect hair health.

Rapid weight loss can trigger telogen effluvium, a temporary condition where bodily stress pushes hair from the growth phase to the resting phase. After a few months, hair will fall out.

Because semaglutide leads to faster weight loss than bupropion-naltrexone, Sodhi said, it may cause more physiological stress, disrupting the hair cycle.

Taking a GLP-1 drug may also suppress a person’s appetite, altering their food choices and intake of important nutrients. Additionally, semaglutide can cause people to experience gastrointestinal issues including vomiting, which could reduce how many nutrients their body processes.

Without the right nutrients, hair health may suffer, said Anthony Rossi, MD, a board-certified dermatologist and dermatologic surgeon at Memorial Sloan Kettering Cancer Center.

Macro nutrients such as protein are important for healthy hair growth. So are some micronutrients, like iron, zinc, some B vitamins, and selenium. "A lot of people who take this medication, whether they know it or not, are in a calorie deficit, and they're probably under-nourished or malnourished,” Rossi said.

Why Are Women More Likely to Lose Hair on GLP-1?

Data on the other popular GLP-1 drugs shows show similar patterns of hair loss and sex differentiation.

In the clinical trial for Zepbound, 7.1% of women experienced hair loss compared to 1.3% in the placebo group. Just 0.5% of men on Zepbound reported the side effect.

The reason for this sex difference isn’t clear. One theory is that rapid weight loss can trigger hormonal shifts in women, including increased levels of testosterone and other androgens, which are linked to androgenetic alopecia—a common form of hair loss.

Another possibility is nutrient deficiency. Rossi said that when people menstruate, they are more likely to become iron deficient. That could contribute to the sex differences seen in the study.

Should This Change Whether You Use GLP-1 Drugs?

Rossi said GLP-1 drugs should not be used to hit a target weight. Instead, they should be a tool to help people improve health outcomes like cardiovascular function and insulin resistance. He added that clinicians can monitor patients' micronutrient panels to help prevent malnutrition.

Sodhi said that for some people, the benefits of GLP-1 may outweigh the risk of side effects like hair loss.

“It is important to recognize that medications like semaglutide are useful drugs,” Sodhi said. "However, the risk-benefit calculus for someone who may be morbidly obese or has very uncontrolled diabetes versus someone who may be using these medications for recreational weight loss—such as wanting to lose 10 pounds prior to a special event—is very different.”