Drug maker Merck & Co. paid $20.4 million last year to more than 2,000 U.S. doctors and healthcare professionals to discuss the company's products and certain healthcare topics with other professionals. The Whitehouse Station, NJ, company posted the new data on payments to individual physicians on its website this week. The company previously disclosed data for the second half of 2009, when it paid $9.4 million to nearly 1,700 professionals. The figures, however, don't include speaker programs tied to Schering-Plough, which Merck acquired in November 2009. Merck spokesman Ron Rogers said the work to prepare for the payment disclosures began before the Schering deal closed, and it's still integrating the Schering data. Merck is among several big drug makers that have begun disclosing physician- payment data in recent years, amid efforts to be more transparent about how they do business.