Seattle-based iMedExchange, which is about to launch a social network for doctors, has raised $2.5 million in angel funding, according to John Cook at the Seattle Post-Intelligencer. Apparently, the site is doctor-approved — of the 40 angel investors, 38 are physicians.

Chief executive Tobin Arthur told Cook he wants to create the online equivalent of a doctors lounge, one that will only be open to practicing physicians. IMedExchange faces competition from another physician social network called Sermo.