US could spend $1 trillion on medications. On top? Weight-loss drugs

Corrections & Clarifications: This story was updated to accurately reflect Eric Tichy's job title. He is a division chair of supply chain management at Mayo Clinic.

Americans' voracious appetite for GLP-1 weight loss drugs has the nation on pace to spend more than $1 trillion on prescription drugs this year, a new report says.

U.S. spending on prescription drugs in 2025 jumped nearly 13% to $915 billion and is projected to surpass $1 trillion in 2026, according to the report by the American Society of Health-System Pharmacists, or ASHP, released April 30.

A major reason drug sales grew so much − the popularity of the weight-loss and diabetes drugs tirzepatide and semaglutide.

Eli Lilly's tirzepatide, sold as Zepbound for weight loss and Mounjaro to treat Type 2 diabetes, is the nation's top-selling drug. It generated wholesale purchases of nearly $63 billion in 2025, the ASHP report said.

Novo Nordisk's semaglutide, sold as Wegovy for weight loss and Ozempic to treat Type 2 diabetes, ranked second at more than $59 billion last year. The No. 3 drug, the blood thinner Eliquis, reached $29 billion in sales, less than half the amount spent on each of the weight-loss drugs, ASHP's report said.

The society analyzed figures from a national database tracking wholesaler purchases from drug manufacturers. Wholesalers then sell the drugs to hospitals, clinics, retail and mail-service pharmacies, home health agencies, long-term care facilities and other health care entities.

The amount consumers pay for the prescription medications changes based on rebates, discounts and insurance coverage.

Consumers pay less. Drug companies collect more

Sales of the weight-loss drugs Zepbound and Wegovy continued to accelerate even as Lilly and Novo cut prices to entice more cash-paying customers. Surveys show nearly half of employer insurance plans cover the anti-obesity drugs. Novo and Lilly have courted consumers without insurance coverage by selling the medications directly through their respective pharmacies or through telehealth providers.

"They are a phenomenon," Eric Tichy, lead author of the ASHP report and a division chair of supply chain management at Mayo Clinic, said of the public's demand for GLP-1 drugs. "The weight-loss aspect makes it a phenomenon when it bumps up against the obesity epidemic we have in the United States."

On April 30, Eli Lilly reported eye-opening quarterly revenue and profit growth fueled by sales of Zepbound and Mounjaro. The first-quarter results came even though Lilly cut prices for Zepbound for U.S. consumers who buy the medication directly from Lilly's pharmacy. In April, Lilly launched its weight-loss pill Foundayo, a medication it expects will buoy sales this year.

Spending on the popular GLP-1 drugs is expected to accelerate with this year's launch of weight loss pills – Novo's Wegovy and Lilly's Foundayo.

Both Lilly and Novo Nordisk are betting daily weight-loss pills will be a popular option for consumers who want to avoid a shot or have been reluctant to take weight-loss medication.

Lilly CEO David Ricks told analysts that price cuts for the popular weight-loss drugs have increased sales.

"Every time we reduce pricing, we see a pretty large expansion," Ricks said.

Although price cuts have enticed cash-paying customers, Lilly's Ricks said it's important to broaden insurance coverage of the anti-obesity drugs.

In late April, Medicare announced a bridge program to begin coverage of GLP-1 weight-loss drugs from July 1 through Dec. 31, 2027. Under the program, Medicare enrollees will pay a $50 monthly copay to get the medications.

Patients use more prescription drugs, drive costs

The ASHP report projects U.S. spending on prescription drugs will jump 10% to 12% this year to surpass $1 trillion.

Beyond the higher sales of GLP-1 drugs, overall drug spending is climbing because of greater use by patients. The report said just about 1% of overall drug spending can be attributed to higher drug prices.

Still, other reports show drug price increases are common. As of Jan. 9, companies raised list prices on more than 850 drugs by a median 4% over 2025, according to data from 46brooklyn Research, a drug pricing nonprofit. Yet some widely used drugs such as Eliquis and Jardiance slashed prices by 43% and 44% respectively, 46brooklyn reported.

In 2025, cancer drugs accounted for the the largest and fastest-growing category of drug spending in clinics and hospitals. Pembrolizumab, sold under the brand name Keytruda, was the top-grossing oncology drug in both clinics and hospitals, the ASHP report said.

One factor driving higher use of prescription drugs might be changes to Medicare coverage policies, Tichy said.

Medicare implemented a $2,100 cap on out-of-pocket drug spending in 2026 for older Americans in Medicare Part D, which covers pharmacy or mail-order prescriptions. The cap is part of the Inflation Reduction Act, the 2022 federal climate and health care bill that also empowered Medicare to negotiate drug prices with pharmaceutical companies.

"That might be driving more use of higher-cost drugs because patients are having to pay less," Tichy said.