SXC Health Solutions Corp. said Thursday that its second-quarter profit climbed 26 percent, as revenue swelled in part due to new customers. But the pharmacy benefits manager's stock price sank nearly 9 percent on a bad trading day for the overall market.

Shares of the Lisle, Ill., company fell $5.29 to $54.63 in heavy trading, as broader indexes tumbled between 4 percent and 5 percent.

JMP Securities analyst Constantine Davides said SXC Health added good business for next year, and he saw nothing "alarming" in the results that would lead to the stock price plunge.

"This is just a terrible tape, and I suspect that you're seeing some momentum money moving to the sidelines," he said.

Credit Suisse analyst Glen Santangelo said in a research note that he continues to be encouraged by the company's "ability to execute on both the acquisition front as well as build its business organically."

SXC Health provides pharmacy benefits management, or PBM, and health care information technology services.

The company earned $21.6 million, or 34 cents per share, in the three months that ended June 30. That compares with earnings of $17.1 million, or 27 cents per share, in the same quarter last year. Adjusted earnings, which exclude certain items, were 38 cents per share.

Revenue more than doubled to $1.21 billion.

Analysts surveyed by FactSet expected earnings, excluding items, of 39 cents per share on $1.13 billion in revenue.

PBM revenue grew due to new customers like HealthSpring and Optima and the acquisition of MedfusionRx, the company said.

Selling, general and administrative expenses also climbed 50 percent to $32.2 million, partially due to transaction-related costs and increased stock-based compensation.

The company lifted its 2011 profit forecast to the higher end of its previous forecast. It now expects adjusted earnings to range from $1.58 to $1.62 per share. That compares to a previous range of $1.55 to $1.62 per share. It raised its revenue expectation to $4.6 billion to $4.7 billion from $4.3 billion to $4.5 billion.

Analysts, on average, expect full-year earnings of $1.62 per share on $4.59 billion in sales.