We love when we come across information that validates our business model. In this case, it’s an article from eMarketer:

The Internet is fast becoming the digital equivalent of the Physician’s Desk Reference. An average of 55.3 million people per month, or 31% of US Internet users, visited a Web site in the health information category in the first quarter of 2007, according to comScore data. That traffic represents a healthy 12% increase over the same period in 2006…

Most of the traffic went to category leader WebMD (17.1 million average monthly visitors), followed by the National Institutes of Health site (9.8 million) and MSN Health (nearly 8.1 million) … MSN Health leaked the fewest visitors to other sites — only 16.8% of the audience went elsewhere, compared with 28.5% of visitors to WebMD…

Many visits were sparked by seeing direct-to-consumer (DTC) ads in other media … After seeing a DTC ad, 27% of respondents talked to their doctor about the drug or condition mentioned, and 89% went online to look for more information on the specific condition or illness. Over six in 10 searched for the prescription medicine itself.

Watch out, WebMD. We’re coming after you…