America's two largest retailers want to deliver prescriptions to your doorstep in as little as a few hours.

Amazon and Walmart are undergoing national expansions in same-day prescription deliveries. They're joining a trend that has gained momentum since the COVID-19 pandemic, with drugstore chains and companies like Instacart and DoorDash rushing to deliver prescriptions as soon as possible.

Fast prescription delivery options are growing as traditional drugstores close and more people use telemedicine or subscription-based care that encourages regular deliveries.

But this trend may run into limits in the complicated U.S. health care system, where drug costs and coverage can outweigh convenience for consumers, some of whom still like visiting a store.

"It takes a lot to change people's behavior when it comes to their health care," said Arielle Trzcinski, a principal analyst with the consulting firm Forrester.

Independent drugstores have done same-day deliveries for years, especially for patients who are homebound or recovering from surgeries, said Brigid Groves, a vice president with the American Pharmacists Association.

CVS Health started same-day deliveries in 2017 and has since expanded its reach. The chain delivered more than 4 million prescriptions through that service in 2023.

Walgreens also does this nationally and offers a service at hundreds of locations that will deliver within two hours.

Instacart got into prescription deliveries during the COVID-19 pandemic when it started a partnership with Costco. The grocery delivery company has since launched same-day delivery partnerships with Wegmans and Publix.

Amazon expects to offer same-day prescription deliveries to nearly half of its U.S. customers by the end of this year. It's adding 20 small pharmacies to distribution centers around the country to improve delivery speeds.

Separately, the company also has opened 10 prescription processing centers in the past few years. It can do same-day deliveries from those as well.

"We're building a modern pharmacy, what we like to think of as a pharmacy in your pocket," Amazon executive Hannah McClellan said at a company presentation last fall.

The Amazon Pharmacy vice president added that this included rapid deliveries and around-the-clock access to pharmacists.

Walmart launched same-day deliveries last fall in six states and expanded earlier this year to every state except North Dakota, where it has no pharmacies. The company allows customers to get their medicines along with groceries or other store items.

It offers several levels of service, including some deliveries in a half hour.

Customer demand drove Walmart's expansion, said Kevin Host, a pharmacy senior vice president. He said prescription deliveries were the top thing customers requested when surveyed by the company.

Host noted that most people pick a pharmacy based on how close it is to their home or whether it has a drive-through window.

"This is just elevating that level of convenience," he said.

Same-day deliveries can help people get started quicker on antibiotics or COVID-19 treatments when they are sick and see a doctor via telemedicine.

McClellan also said that customers who get their prescriptions quickly are more likely to take them. She said Amazon was doubling down on same-day deliveries this year and has "big plans to continue to build and scale those capabilities in the years to come."

Patients may like convenience, but they like saving money even more.

Same-day deliveries can come with additional fees. People who consider them will want to know whether they are getting a better deal on their medicines, Trczinski said. She noted that this is especially true with so-called maintenance prescriptions that are refilled repeatedly.

People with insurance who are taking those maintenance drugs may already have them delivered, noted Andrew Mulcahy, a senior health economist with the nonprofit research organization RAND Corp.

"The practical implications of these kinds of programs will be very muted," he said.

Customers also will have to trust that their regular prescriptions get delivered on time and are covered by their health insurer, especially if they switch pharmacies for deliveries. Some pharmacy benefit managers limit coverage outside certain pharmacies.

Drugstore pharmacists also have started providing more care and working with customers to manage conditions like high blood pressure. These things give people more reasons to visit a store.

Plus, some people just prefer going to drugstores. Don Watson says he might consider prescription deliveries "maybe 10 years from now when I'm not able to do it myself."

The 72-year-old Indianapolis resident said as he left a Walgreens store recently that he has no problem picking up prescriptions.

"Sometimes the wait can be a little long ... that's my only gripe," he said.

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Haleluya Hadero contributed to this report.

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