Rob Lamberts, MD

"I tend to obsess on it a little too much," admits Lamberts, 47, adding that acclaim from major media outlets such as The New York Times has turned up the pressure to stay active.

That obsession inspires Lamberts to update his blog at least three times a week—usually in the morning, before work—while still maintaining his load of 25 to 40 patient visits a day, hospital rounds once or twice a week, and time with his four children. He likes having a constant outlet for his thoughts, but he knows that, as a physician blogger, he shoulders additional responsibility with each post.

A recent study by researchers from the University of Pennsylvania noted that blogs "provide a new route for communicating substantial, evidence-based health information to the public" and are particularly useful for more isolated, rural physicians, who may have few other outlets for support and advice.

But the study also found that many blogging physicians appear to leave their ethical obligations offline. Of the study's 271 blogs written by healthcare professionals across the U.S. (75 percent of them by physicians), 42 percent described individual patients. Approximately 1 in 6 contained enough information for patients to identify their doctors or themselves, and 1 in 10 promoted a specific product without including conflict-of-interest disclaimers.

The study, published in the Journal of General Internal Medicine, cited several examples of physician rants, including this one from the blog Panda Bear MD: "She was a stupid, lazy, selfish woman all of which characteristics are personal problems, not medical issues or barriers to care." (Panda Bear MD has been discontinued, and its author could not be reached for comment.)

"Health professionals who share private thoughts in public settings risk revealing confidential patient information or otherwise reflecting poorly on the profession," the authors wrote. The key, perhaps, is in recognizing that the internet is the most public of all possible settings.

Howard Luks, MD, a sports medicine orthopedist in New York who blogs at http://www.howardluksmd.com, says he usually avoids patient issues altogether, focusing instead on the business, politics, and future of medicine.

"Most bloggers try very hard to disguise or to protect patients' identities," Luks says. "I don't need to rant online about a patient I had in the office who annoyed me. That's not my goal in blogging."

Though primary care physicians may be a thinning breed, their blogs are likely heading in the opposite direction. There are already more than 70 million blogs on the web, with an average of 120,000 new ones emerging each day, according to the web-tracking service Technorati.

But as medical blogs continue to proliferate, guidance on their use remains scarce—a fact bemoaned by the study's authors.

The American Academy of Family Physicians has no plans to offer blogging guidelines, according to Jason Mitchell, MD, assistant director of the AAFP's Center for Health Information Technology. Mitchell denounces the study's call for professional associations to create blogger guidelines.

"An ethical code has existed for physicians for hundreds of years," he says. "If that code is broken by writing, speaking, e-mailing, or blogging, the physician should be held accountable. Blogging brings no new rules to the table in terms of ethics."