If you’ve followed the buzz around semaglutide, you know that it can help with weight loss (as Wegovy) and Type 2 diabetes (as Ozempic). But the medication is now stepping into a brand-new role: treating liver disease caused by fatty buildup.

In August 2025, the FDA green lit Wegovy for adults with MASH, a liver condition, as well as moderate-to-advanced fibrosis. MASH — which stands for metabolic dysfunction-associated steatohepatitis — is marked by a buildup of fat in the liver that causes inflammation and scarring. The condition was previously known as non-alcoholic steatohepatitis (NASH).

The FDA approval of Wegovy for MASH is an accelerated one. It’s based on results of a large trial that’s about one third complete. Nevertheless, it’s an exciting milestone. This is only the second medication to get approval as a treatment for MASH, and it’s the first medication of this type.

‍

Semaglutide is a GLP-1 receptor agonist, a medication that mimics a natural hormone that the body uses to regulate appetite, insulin, and digestion. It’s sold as Ozempic (to treat diabetes) and Wegovy (for weight loss). And its list of benefits is growing.

Clinical trials show semaglutide works for severe liver disease

The evidence for semaglutide’s effect on advanced fatty liver disease comes from several major clinical trials that put the medication to the test.

The most recent of these is a large, global study published in the New England Journal of Medicine in April 2025, known as the ESSENCE trial. In the study, adults with MASH and liver fibrosis (scarring) were treated weekly with semaglutide or placebo (a sham medication) for over a year.

Here’s what happened:

• Improved liver inflammation and scarring: People taking semaglutide were almost twice as likely as those on placebo to see their liver inflammation improve without worsening scarring. Semaglutide also helped improve liver scarring without making the inflammation worse.
• Weight loss: People taking semaglutide also lost a significant amount of weight, with an average drop of around 11% compared to just 2% in the placebo group.
• Better blood sugar, cholesterol, and liver health: Semaglutide also helped lower blood sugar, reduced markers of inflammation, and improved liver enzymes.
• Few side effects: Side effects were generally mild and mostly related to digestion, like nausea and diarrhea. Very few people stopped the medication because of side effects.

We should add that the trial is still underway. These results were analyzed at 72 weeks, but the trial will continue for a total of 240 weeks (about 4.5 years).

Earlier research already hinted at semaglutide’s benefits for liver health. A phase 2 study released in 2020 showed that semaglutide could clear the inflammation and fat from the liver in many people with MASH. And when researchers combined results from several trials in 2023, they found a clear pattern: semaglutide helped people lower the amount of fat in their liver and slow down inflammation.

Put together, these studies show that semaglutide is doing more than just lowering blood sugar or helping with weight: It is improving the health of the liver itself.

How semaglutide works for MASH and liver fibrosis

MASH is when the liver is inflamed from fat buildup. This inflammation leads to scar tissue (fibrosis) and an increased risk of liver cirrhosis, liver failure, and heart problems.

Semaglutide works by improving both the inflammation and the scarring, according to the researchers who led the ESSENCE study (mentioned above). Here’s how this happens:

1. Anti-inflammatory effects: Semaglutide significantly calms liver inflammation without worsening scarring.
2. Anti-scarring effects: Semaglutide also reversed some liver scarring, without worsening inflammation.

Semaglutide also has whole-body effects that improve metabolic health, like lowering weight, improving blood sugars, and regulating insulin. These bigger changes treat the underlying cause of MASH (fat buildup in the liver).

So, what’s the takeaway? Semaglutide treats both the cause and the damage of MASH. The medication’s main goal is to improve metabolic health and reduce inflammation. But it also slows down scarring.

This combo effect is a major step forward — especially since semaglutide works without causing serious side effects for most people.

As the ESSENCE trial continues, researchers will be able to say whether the improvements in liver inflammation and scarring seen after 72 weeks result in improved outcomes longer term.

Common side effects of semaglutide

Like many medications, semaglutide can cause some side effects. Most tend to be mild and manageable. The most common ones are digestion-related, like nausea, diarrhea, or constipation. These usually show up when you first start the medication. And they often get better with time as your body adjusts.

In the large liver disease trials (mentioned above), only a small number of people had to stop semaglutide because of side effects. That’s encouraging, since it means most people are able to stay on treatment long enough to get the benefits.

If you do experience side effects, there are strategies that can help. For example, you can start at a lower dose and then gradually increase how much you take to give your body time to adapt to the medication.

Who should and shouldn’t take semaglutide for MASH?

While semaglutide is a great option for many, it's not for everybody. It’s only FDA approved for people who don’t have cirrhosis from MASH. So, if you have MASH and cirrhosis, then semaglutide probably isn’t for you.

You should also avoid semaglutide if you have a history of certain conditions like:

• Pancreatitis
• Certain thyroid conditions
• Severe gastrointestinal (GI) disease

And, if you’re pregnant or nursing, you shouldn’t take semaglutide.

As always, it’s best to speak with your healthcare team before deciding to start taking any medications. It’s important to discuss your health with someone who knows your full medical history.

The bottom line

The FDA’s approval of semaglutide (Wegovy) for liver disease marks a watershed moment for people with MASH and liver fibrosis. Backed by strong evidence, this once-weekly injection tackles both inflammation and scarring in the liver, along with metabolic benefits. The medication may not be right for everyone. But it’s a promising and well-studied option that could transform the outlook for people with advanced fatty liver disease.

‍