Medco Health Solutions and Verizon Wireless last month released a mobile application that guides smartphone users to the locations where they can purchase the lowest-cost prescription drugs.

Verizon said the new Medco Pharmacy mobile app can also identify potentially harmful drug interactions based on Medco members' medication histories.

Medco, which provides pharmacy services to more than 65 million customers, said its pharmacy mobile app is available for BlackBerry and Android smartphone users. It provides information about out-of-pocket costs for any prescription drug and lower-cost options specific to a person's prescription drug plan, even if a patient is being treated by several doctors or fills prescriptions at many different pharmacies.

Medco said that half a million prescriptions that have lower-cost options are written each day.

The Medco Pharmacy mobile app is built on Medco's My Rx Choices prescription savings and patient safety program, which was launched online in 2006. To use the app, patients must first register at the Medco website . Once registered, their medication histories and drug plans are made available online.

This version of this story was originally published in Computerworld's print edition. It was adapted from an article that appeared earlier on

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