UPDATE 1-Athenahealth IPO raises $113 mln, above forecast

(Adds background, initial market valuation, analyst comment)

NEW YORK, Sept 19 (Reuters) - Athenahealth Inc, which provides Internet-based office services to physicians, on Wednesday raised $113 million with an initial public offering that was priced $2 higher than a forecast range.

The offering of 6.28 million shares sold for $18 per share, compared with a forecast range of $14 to $16, according to an underwriter.

The IPO had attracted widespread interest from investors, primarily because the company has strong revenue growth, recurring revenue and its services are highly sought after.

The company's services help physician offices with administrative tasks such as billing, insurance claims and other back office functions.

Athenahealth's offering price gives the company an initial market capitalization of nearly $570 million.

Based in Watertown, Massachusetts, the company plans to use net proceeds from the offering to pay down debt, boost capital and facilitate future access to public equity markets.

Led by Goldman Sachs and Merrill Lynch, underwriters have the option to purchase an additional 943,000 shares to cover overallotments.

The company's shares are expected to debut on Nasdaq tomorrow under the symbol "ATHN." (ATHN.O: Quote, Profile, Research, Stock Buzz)