A new class of 'game-changer' weight-loss drugs exploded in popularity in 2022, and supply can't keep up

• Medications like semaglutide and tirzepatide are gaining popularity as weight loss treatments.
• Initially used to treat diabetes, the drugs help moderate appetite and reduce cravings.

A new category of weight loss medications, repurposed from diabetes treatment, are seriously changing how we think about and approach weight management.

In 2021 the medication semaglutide, called a "game changer" in the industry, officially got the FDA's approval to be prescribed for weight loss. In 2022, it has soared in popularity, becoming more widely used and spurring more research. In the past year, another promising drug has also been eyed for approval as a weight loss treatment.

Here's what we know about the drugs, from their effectiveness to side effects.

Semaglutide became so popular it prompted shortages

Semaglutide, originally used to treat diabetes, was FDA-approved for weight loss in 2021 and is sold under the brand names Wegovy and Ozempic.

The medication acts on a specific hormone called GLP-1 that controls appetite, so patients taking the drug feel more full. It also helps with the production of insulin, a hormone that regulates blood sugar levels. Research suggests it can help patients lose significant weight, and keep it off if they keep taking the drug.

A similar medication, liraglutide, was FDA-approved for weight loss in 2014 — the main difference with semaglutide is that it's longer-lasting, administered in weekly instead of daily injections, and evidence suggests it leads to more weight loss.

High demand for semaglutide prompted shortages by late 2021, which have continued into this year, according to the FDA.

In summer 2022, semaglutide shortages in Australia were linked to a TikTok trend of users sharing weight loss experiences with the drug, sometimes misleadingly.

Elon Musk added to media buzz by announcing on Twitter he had been taking it for weight loss. Combined with rumors that the drug was the latest Hollywood weight loss hack, experts voiced concerns that all the hype could make the medication harder to access for patients who need it, according to the Wall Street Journal.

Patients say it helps cut cravings for junk food and alcohol

One factor in semaglutide's popularity has been eye-catching anecdotes from patients who said it caused them to stop craving foods like bacon and sweet treats.

The medication makes it easier to practice moderation and portion control, according to patients who take it. The drug works in part by changing the brain's reward center, disrupting the allure of hyperpalatable foods high in salt, fat, and sugar.

As a result, it has also shown potential for curbing other types of addiction — some patients have found it reduces their desire to drink alcohol and helps them cut back on drinking.

Tirzepatide has promising results but isn't yet approved for weight loss

In June 2022, a similar diabetes medication called tirzepatide made headlines after research showed people taking it lost 20% of their body weight in 16 months, Insider's Rachel Hosie reported.

It works similarly to semaglutide, but hasn't yet received FDA approval for weight loss.

"We do expect that it will be approved for the treatment for obesity," endocrinologist and obesity medicine specialist Dr. Scott Isaacs previously told Insider, although it's not clear how soon.

Patients can still access the drug, however, since it has been approved for diabetes, allowing doctors to prescribe it for obesity if they think it will help.

Tirzepatide grew in popularity in 2022 in part because of a discount making the drug more affordable, but long term access is a concern because insurance rarely covers weight loss medication, Isaacs said.

Weight loss drugs are considered safe, but can cause side effects like nausea

Both semaglutide and tirzepatide work for weight loss by decreasing appetite, making patients less likely to overeat. But they can also cause unpleasant symptoms including nausea and diarrhea.

In some cases, the hunger-suppressing effects can make it hard for people to enjoy food, causing disgust or indigestion when they try to eat previously-beloved treats like chocolate, fried chicken, or even coffee, Insider's Anna Medaris previously reported.

More research is needed to assess the long-term effects of the medications, but current evidence suggests they can be used safely and effectively to treat patients, Dr. W. Scott Butsch, director of obesity medicine at the Cleveland Clinic, told Insider.