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 American Society of Health-System Pharmacists (ASHP) report 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 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 now cover the anti-obesity drugs. Novo and Lilly have also courted consumers without insurance by selling the medications directly through their respective pharmacies or through telehealth providers.
“They are a phenomenon,” said Eric Tichy, lead author of the ASHP report and chair of supply chain management at Mayo Clinic. “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 strong quarterly revenue and profit growth fueled by Zepbound and Mounjaro sales — even after cutting Zepbound prices for U.S. consumers buying directly from Lilly’s pharmacy. In April, Lilly also launched a weight-loss pill, Foundayo, which it expects to buoy sales further this year.
Spending on GLP-1 drugs is expected to accelerate further with the launch of weight-loss pills from both companies — Novo’s Wegovy pill and Lilly’s Foundayo. Both firms are betting daily oral options will appeal to consumers who want to avoid injections or have hesitated to start weight-loss medication.
Lilly CEO David Ricks told analysts that price cuts have been effective.
“Every time we reduce pricing, we see a pretty large expansion,” Ricks said.
Although price cuts have enticed cash-paying customers, Ricks said broadening insurance coverage remains important. Earlier this month, Medicare announced a bridge program to begin GLP-1 coverage for weight loss from July 1 through Dec. 31, 2027. Under the program, Medicare enrollees will pay a $50 monthly copay.
Patients Using More Drugs — Not Just Paying More for Them
The ASHP report projects U.S. prescription drug spending will jump 10 to 12% this year to surpass $1 trillion.
Beyond GLP-1 growth, overall spending is climbing because more patients are using more drugs. The report found that just about 1% of the spending increase can be attributed to higher drug prices.
Still, other data show price hikes remain widespread. As of Jan. 9, companies raised list prices on more than 850 drugs by a median 4% over 2025, according to 46brooklyn Research, a drug pricing nonprofit. Meanwhile, some widely used drugs like Eliquis and Jardiance slashed prices by 43% and 44% respectively.
In 2025, cancer drugs accounted for the largest and fastest-growing category of drug spending in clinics and hospitals. Pembrolizumab — sold as Keytruda — was the top-grossing oncology drug in both settings, the ASHP report said.
One factor driving higher prescription use may be Medicare policy changes. In 2026, Medicare implemented a $2,100 cap on out-of-pocket drug spending for enrollees in Part D, which covers pharmacy and mail-order prescriptions. The cap is part of the Inflation Reduction Act, the 2022 law that also gave Medicare the power to negotiate drug prices directly with pharmaceutical companies.
“That might be driving more use of higher-cost drugs because patients are having to pay less,” Tichy said.