The company said prime members would get additional savings when paying without insurance. Customers can pay as low as $1 per month for select medications, including drugs to treat diabetes and blood pressure, and will get free two-day delivery.

The e-commerce giant launched an online pharmacy in November for delivering prescription medications in the United States and stirring up competition with drug retailers such as Walgreens Boots Alliance, CVS Health and Walmart.

Shares of pharmacy chains and drug wholesalers fell in morning trading as Amazon's launch of online pharmacies has been a threat to brick-and-mortar pharmacies at a time when e-commerce has surged due to COVID-19 restrictions.

Shares of Walgreens and CVS were down 1.2% each, and those of drug distributors AmerisourceBergen Corp and McKesson Corp fell 1% and 1.7%, respectively.

Amazon is also looking at launching physical pharmacies in the United States, the Insider reported last month.

Under the new offering, customers can search for their medication by name and find out if it's eligible for a six-month supply and what the price it will be when using the Prime prescription savings benefit, the company said.

It added that the supplies would be available only for customers who have a prescription from their healthcare providers.

Amazon has been trying to enter the pharmacy market since its 2018 acquisition of PillPack, which is a platform used by customers who need pre-sorted doses of multiple drugs.

Rival Walgreens offers free same-day and next-day delivery options for drugs.

(Reporting by Noor Zainab Hussain and Dania Nadeem in Bengaluru; Editing by Amy Caren Daniel)