Prestige Brands (PBH) nearly doubled its fourth-quarter profit on strong over-the-counter product sales, helped by acquisitions and growth of its five core brands.

The Irvington, N.Y.-based maker of over-the-counter healthcare, household cleaning and personal care products posted net income of $6.4 billion, or 13 cents a share, compared with $3.3 billion, or 7 cents a share, in the same quarter last year.

Excluding one-time items, the company earned 18 cents a share, matching average analyst estimates polled by Thomson Reuters. The results were weighed down by a 57% jump in operating expenses.

Revenue for the seller of products such as Clear Eyes, NightGuard, Dermoplast, Sleep-Eze, Comet and Spic and Span was $96.4 million, up 37.8% from $66.4 million a year ago, beating the Street’s view of $95.3 million.

Prestige CEO Matthew Mannelly called 2011 an extremely productive and transformative year, noting the company is pleased with its brand growth and integration of Blacksmith Brands and Dramamine.

Brands grew 20.6% during the quarter, up from 14.2% in the third quarter, 3.4% in the second-quarter and negative 6.4% in the first quarter. The company’s organic five core over-the-counter brands climbed 8.4%. Its total OTC Healthcare segment jumped 66.5% to $71.6 million.

During the fiscal year, Prestige paid $17.5 million in debt, bringing total indebtedness as of March 31 to $492 million.

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