WHITEHOUSE STATION, N.J. (AP) — Merck & Co. says its fourth-quarter profit fell 7 percent as generic competition slashed sales of its blockbuster allergy drug Singulair and the drugmaker took sizeable restructuring and acquisition charges.

The world’s third-biggest drugmaker by revenue says net income was $1.4 billion, or 46 cents per share, down from $1.51 billion, or 49 cents per share, a year earlier.

Excluding one-time charges totaling $1.14 billion, net income was $2.54 billion, or 83 cents per share, 2 cents more than analysts polled by FactSet were expecting.

The maker of Januvia and other diabetes pills says revenue totaled $11.74 billion, down 5 percent from 2011′s fourth quarter. Analysts expected revenue of $11.47 billion.

Merck, which is based in Whitehouse Station, N.J., forecast 2013 earnings per share of $3.60 to $3.70, excluding charges.