NEW YORK ( TheStreet) -- Hospira ( HSP) shares were falling almost 20% after the drugmaker cut its 2011 earnings forecast.

Hospira said it expects 2011 adjusted earnings of $2.95 to $3.05 a share. Over the summer, the company said it expected earnings of as much as $4 a share.

"While recently launched product sales continue to drive top-line growth, we were extremely disappointed in the third quarter by developments related to our quality-improvement initiatives that resulted in a significant slowdown of production and an associated impact on our operating performance," said F. Michael Ball, Hospira's CEO, in a statement.

The company said it expects third-quarter adjusted earnings of 66 cents a share on sales of $977 million, far lower than analysts' estimates.

Hospira blamed the slowdown on quality actions it took at its manufacturing plant in Rocky Mount, N.C., in response to a Food and Drug Administration warning letter in 2010.

Hospira shares were down $7.21, or $19.3%, to $30.15. The stock touched a 52-week low of $29.16 earlier Tuesday. Its 52-week high is $60.49.

-- Written by Joseph Woelfel

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