FDA Approves SINGULAIR(R) for Seasonal Allergic Rhinitis

Market Wire, 20050229

Allergic Rhinitis in the United States

Allergies are among the most common chronic conditions in the United States. More than 50 million people in the U.S. suffer from some form of allergic rhinitis. Seasonal allergic rhinitis is associated with specific triggers such as tree, grass and weed pollen. Many people with allergies also suffer from other upper and lower respiratory system conditions, including asthma, sinusitis, pharyngitis and ear infections.

About Merck

Merck & Co., Inc. is a leading research-driven pharmaceutical products and services company. Merck discovers, develops, manufactures and markets a broad range of innovative products to improve human and animal health, directly and through its joint ventures.

Merck Forward-Looking Statement

This press release contains "forward-looking statements" as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements involve risks and uncertainties which may cause results to differ materially from those set forth in the statements. The forward-looking statements include statements regarding product development and product potential. No forward-looking statement can be guaranteed, and actual results may differ materially from those projected. Additional detailed information concerning a number of factors that could cause actual results to differ materially is available in Item 1 of Merck's Annual Report on Form 10-K for the year ended Dec. 31, 2001, in its periodic reports on Form 10-Q and in its reports on Form 8-K (if any). Copies of these forms are available on request to Merck's Office of Stockholder Services.

Prescribing information is attached and is also available at www.merck.com or www.singulair.com. (1) IMS Health, National Prescription Audit Plus(TM), TRXs, Retail data only

(2) IMS Health National Prescription Audit Plus(TM), All Channels, November 2002