Thread by @NBCNews

A new class of weight-loss drug is giving some patients with obesity new hope that they’ll be able to lose weight and improve their health, but doctors say relatively few of the country’s millions of eligible patients are taking them. #NBCNewsThreads (1/9) nbcnews.to/3HoAu1U

The drugs mimic a hormone called GLP-1, which tells the pancreas to secrete more insulin to control blood sugar. They’re not new to medicine; they’ve been used to treat Type 2 diabetes for years. (2/9)

It’s still unclear exactly how the drugs help with weight loss. Thomas Wadden, director of Penn Medicine’s weight and eating disorders program, said they seem to slow down stomach-emptying so people stop eating sooner and feel full longer. (3/9)

Wegovy was approved last year for patients with certain body mass indexes or weight-related conditions. The weekly self-injectable helped patients lose about 15% of their body weight over 16 months, according to studies. (4/9)

Tirzepatide, a newer GLP-1 medication, appears to be even more effective. A study published in the New England Journal of Medicine found it helped patients lose more than 20% of their weight over 72 weeks. (5/9)

Side effects most commonly include nausea, vomiting, diarrhea and stomach pain. And experts stress the drug is not a magic bullet: “I don’t care how wonderful the drug is, it will not work for everyone,” says Dr. Li, director of UCLA’s Center for Human Nutrition. (6/9)

Dr. W. Scott Butsch said the drugs' underuse all comes down to money. Insurance companies push back against coverage for weight loss drugs, arguing that obesity is not a disease but a behavioral problem, Butsch said. (7/9)

Qamara Edwards lost 75 pounds in a 17-month study for Wegovy, but her insurance wouldn’t pay for it after it was approved for prescription. “I may not be able to continue because insurance and the pharmaceutical industry feels like weight loss is not a medical issue.” (8/9)

Those who can afford to pay out of pocket can get the medications, but studies show that obesity rates are higher among those who live in poor communities. That means that “those who really need these drugs are likely not going to get them,” Dr. Butch said. (9/9)