Merck & Co. posts an 90 percent drop in third-quarter profit, due to large charges for its $41.1 billion acquisition of Schering-Plough Corp.

The world's second-biggest drugmaker by revenue had net income in the quarter of just $341.6 million, or 11 cents per share. That's down from $3.42 billion, or $1.61 per share, a year earlier.

Excluding one-time charges worth 74 cents per share, Merck would have made 85 cents a share.

That's three cents more than analysts expected.

The maker of Januvia for diabetes and Singulair for asthma and allergies says its revenue was $11.12 billion, up 84 percent from $6.05 billion in 2009's third-quarter, when it didn't have revenue from Schering-Plough's products.

Analysts were expecting $11.24 billion.