Such is life when the overall market exhibits signs of the bipolar disorder we diagnosed last week.

FORBES: The Oil Stock Swing

The attention deficit hyperactivity disorder drug, which is already on the market for sleepiness under the name Provigil, had caused one possible case of Stevens-Johnson Syndrome, a rare skin reaction.

FORBES: Blindsided

ResMed, in San Diego, California, ranks second in the U.S. market for devices that help people suffering sleep apnea, a disorder that affects the breathing.

FORBES: The hot ones

It is already on the market to treat rheumatoid arthritis and Crohn's disease, a gastrointestinal disorder.

FORBES: J&J Edges Up On The Itch

The two biotech firms have finished their safety review of Tysabri, the multiple sclerosis drug that the companies pulled from the market on Feb. 28 after it was linked to a rare brain disorder.

FORBES: Tysabri Still Down, But Not Out

That pitch could extend the market beyond the 30 million men in the U.S. who have the disorder and into the ranks of healthy men looking for a pick-me-up.

FORBES: Let's Talk About Sex

In 2005, the company pulled its multiple sclerosis drug, Tysabri, from the market after a patient who was taking the drug in conjunction with another medication died of a rare brain disorder.

FORBES: Magazine Article