AdvancePCS Stockholders Approve Merger with Caremark Rx Inc.

Business Editors/Health/Medical Writers

IRVING, Texas--(BUSINESS WIRE)--March 22, 2004

AdvancePCS (Nasdaq: ADVP) stockholders today approved all proposals presented in the joint proxy statement, mailed on or about Feb. 17, 2004 to stockholders of AdvancePCS, including the previously announced merger between Caremark Rx Inc. (NYSE: CMX) and AdvancePCS. Caremark stockholders will also vote today, among other things, to approve the issuance of shares of Caremark common stock to AdvancePCS stockholders in the merger.

On Sept. 2, 2003, Caremark Rx and AdvancePCS announced the signing of a definitive merger agreement. Under the terms of the definitive agreement, Caremark Rx will acquire 100 percent of AdvancePCS' outstanding stock. AdvancePCS stockholders will receive value equivalent to 2.15 shares of Caremark Rx stock for each AdvancePCS share, to be paid in Caremark Rx stock (90 percent) and cash (10 percent).

About AdvancePCS

AdvancePCS (www.advancepcs.com) is the nation's leading provider of health improvement services. AdvancePCS offers health plans a wide range of health improvement products and services designed to improve the quality of care delivered to health plan members and manage costs.

The company's capabilities include integrated mail service and retail pharmacy networks, innovative clinical services, customized disease management programs, specialty pharmacy, outcomes research, information management, prescription drug services for the uninsured and online health information for consumers. AdvancePCS clients include Blue Cross and Blue Shield organizations, insurance companies and HMOs, Fortune 500 employers, Taft-Hartley groups, third-party administrators, state and local governments, and other health plan sponsors.

AdvancePCS is listed as both a Fortune 500 and a Fortune 500 Global company. AdvancePCS is ranked by Fortune magazine as one of America's 100 fastest-growing public companies and is included on the Forbes Platinum 400 list of best big companies. AdvancePCS earned the No. 3 spot on the Barron's 500 list of best performing companies.

Additional information about AdvancePCS is available on the World Wide Web at www.advancepcs.com.

About Caremark Rx Inc.

Caremark Rx Inc. is a leading pharmaceutical services company, providing comprehensive drug benefit services through its affiliate Caremark Inc. to more than 1,200 health plan sponsors and their participants throughout the United States. Caremark's clients include corporate health plans, managed care organizations, insurance companies, unions, government agencies and other funded benefit plans. The company operates a national retail pharmacy network with more than 55,000 participating pharmacies, four state-of-the-art mail service pharmacies, the industry's only FDA-regulated repackaging plant and 19 specialty distribution mail service pharmacies for delivery of advanced medications to individuals with chronic or genetic diseases and disorders.

Additional information about Caremark Rx is available on the World Wide Web at www.caremarkrx.com.

Safe Harbor Statement

This press release contains statements that constitute "forward-looking statements" within the meaning of the Securities Act of 1933 and the Securities Exchange Act of 1934, both as amended by the Private Securities Litigation Reform Act of 1995. These statements are based on the current expectations of management of both companies. There are a number of risks and uncertainties that could cause actual results to differ materially from the expectations of management. You are encouraged to consult the filings which each of Caremark Rx Inc. and AdvancePCS make with the Securities and Exchange Commission for more information concerning such risks and uncertainties. You are cautioned not to place undue reliance on these forward-looking statements which speak only as of the date stated, or if no date is stated, as of the date of this press release.