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What: Shares of home-health-care specialist Lincare Holdings (Nasdaq: LNCR) were in V-fib today, losing as much as 10% in intraday trading on heavy volume.

So what: During earnings season, investors can be a little like kids in a candy shop -- when they don't get what they want, they throw a tantrum. Though sales of $449 million topped analysts' estimates, Lincare's second-quarter profit didn't live up to expectations as it clocked in at $0.45, versus estimates of $0.51. The company is wrangling with Medicare payment changes that started this year and also said that there were a variety of other factors that drove higher costs during the quarter. That list included increases in specialty pharmacy drug volumes and costs associated with new expansion plans.

Now what: Lincare CEO John Byrnes put a positive spin on the quarter, noting that the company "made steady progress in the first half of 2011 in executing certain new strategic initiatives that will provide future expansion for [the] business." The earnings miss is unusual for Lincare, which has measured up to analysts' expectations in each of the previous four quarters, so current investors may want to stick around to see if things are righted in the coming quarters.

For those still on the sidelines, the stock's 12.5 trailing earnings multiple may look pretty attractive, but be on the lookout for analysts lowering their 2011 guidance after the weak second quarter.

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Fool contributor Matt Koppenheffer does not have a financial interest in any of the companies mentioned. You can check out what Matt is keeping an eye on by visiting his CAPS portfolio, or you can follow Matt on Twitter @KoppTheFool or Facebook. The Fool's disclosure policy prefers dividends over a sharp stick in the eye.