Earnings surprises come in one of two flavors. Yesterday, shares of drugmaker Cephalon (NASDAQ:CEPH) rose almost 7%, after the company announced investors' favorite flavor.

Cephalon now expects $4.40 to $4.50 per share in adjusted income for 2007, $0.50 a share higher on each end of the range. Though it didn't increase overall sales guidance for the year, Cephalon partly attributed its higher earnings guidance to higher sales of its pain franchise drugs, Actiq and Fentora.

This isn't the first time that Cephalon has raised its earnings guidance in the past 16 months. I've previously mentioned the drugmaker's fondness for revising forward estimates upward, so don't be surprised if the company guides for higher sales growth later in the year.

Cephalon seems to be experiencing a much more rosy outlook for its pain franchise drugs than it expected when Actiq lost its marketing exclusivity in November of last year. Last quarter, its pain franchise drug sales actually grew 56%, despite Barr's (NYSE:BRL) introduction of a generic version of Actiq. The drug probably won't fare so well in the first quarter, but nevertheless, Cephalon is doing a good job of marketing Actiq. (Perhaps too good of a job, sometimes.)

Whatever the reason for the higher earnings guidance, there's rarely a reason to complain about it. Cephalon's management team deserves kudos for how it's controlled expenses and handled the marketing of its top compounds. Shares of Cephalon are trading 60% above their 52-week lows, and for approximately 20 times the company's earnings guidance for the year. With no serious competition for its lead compounds in the near term, investors should take a look at the well-run pharma.

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Barr Pharmaceuticals is a Stock Advisor selection.

Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool has a disclosure policy.