7 Stocks you need to know for Tuesday

Merck (MRK | news | PowerRating | PR Charts ) lost 14.7% and Schering-Plough (SGP | news | PowerRating | PR Charts ) plunged 26% after a panel of experts urged doctors to cut prescriptions of Vytorin and Zetia, their jointly marketed cholesterol drugs.

Cal-Maine Foods (CALM | news | PowerRating | PR Charts ) dropped 11.8%, despite reporting earnings that more than tripled from a year ago.

Western Union (WU | news | PowerRating | PR Charts ) partnered with Radio Shack (RSH | news | PowerRating | PR Charts ) to allow users to transfer money through their cell phones.

SanDisk (SNDK | news | PowerRating | PR Charts ) rose 6.6% after a strong showing by memory chip makers in Asia overnight.