While watching their brother battle Amyotrophic Lateral Sclerosis, an incurable neurodegenerative disease, Benjamin and James Heywood noticed a great day-to-day need of the patients and people supporting them -- communication.

In response, the Heywood brothers, along with friend Jeff Cole, launched an online community last year, PatientsLikeMe.com, where ALS patients and their families can communicate. Through the site, patients can track their individual progress and compare potential treatments for not only ALS, also known as Lou Gehrig's disease, but also Multiple Sclerosis, Parkinson's disease and soon HIV and AIDS.

"The more patients we have sharing in each community, the better the information set is and the better for them to manage their disease," Benjamin Heywood said.

Start-ups such as PatientsLikeMe Inc. that are pushing a consumer approach to health care are sprouting again with support of venture capitalists. It's a revival from the dot-com boom days, when many similar sites took off before dying away shortly after. Now that high-speed Internet is the norm, advertising has proven its worth online and social networking is king, investors are betting on a warmer market reception.

Venture capitalists have so far invested a total of about $90 million in PatientsLikeMe and related start-ups LifeMed Media, Waterfront Media and HealthCentral Network Inc. But these young companies are going head-to-head against Internet giants like Microsoft Corp. and Google Inc., which recently announced the creation of their own health-focused Web ventures. And former America Online co-founder Steve Case has entered into this market with his latest company, Revolution Health Group LLC.

Looking Beyond WebMD

Each new brand also faces an established leader: WebMD Health Corp., which consistently ranks first in this space, according to Internet research group comScore Inc. Its Web site had 15.6 million unique visitors in December, up 15% from a year ago. WebMD had revenue of $238.6 million for the first nine months of 2007, according to its latest quarterly earnings report, up from $173.3 million for the same period in 2006.

"WebMD is almost entirely advertising," said Citigroup Director of Internet Research Mark Mahaney. "It's actually got one of the highest earnings growth profiles in the Internet sector."

WebMD, which was first formed in 1996 and was originally venture-backed, merged with Healtheon Corp. in 1999. The company, which has grown through a steady stream of acquisitions through the years, used those mergers in part to cut operating costs and adapt to change during lean times. While the company did not follow a straight path to profitability, it now has a bright outlook, analysts say. WebMD continues to evolve with the Internet, unrolling new interactive tools and content to match its new competitors.

Rather than try to unseat WebMD, some venture-backed start-ups are working to define their own niches. As with PatientsLikeMe, LifeMed Media targets specific disease sufferers. Its Web site, DLife.com, serves diabetes patients with information, expert tips, blogs and video clips that are broadcast in physician office waiting rooms. Dlife is growing fast - it had 624,000 visitors in December, up 303% from a year ago -- but it's still small, ranking at only No. 36 on comScore's health information category list.

LifeMed Media has raised $15.7 million to date from Battery Ventures, Cross Atlantic Partners and Milestone Venture Partners. When the company announced its Series C round in November 2006, it said it was generating revenue from its Web and television content. At that time, one of the company's investors said the company was close to breaking even from that revenue. LifeMed Media did not respond to requests for comment for this article.

Unlike other sites in this space, PatientsLikeMe does not plan to sell advertising space. The company is currently pursuing partnerships with pharmaceutical, medical device and non-profit organizations to share access to its site's information. Heywood declined to disclose how many deals the company currently has in place and the revenue the company has generated.

PatientsLikeMe, which was incorporated in December 2004, has raised about $5.75 million to date through Invus Group, Collaborative Seed & Growth Partners, Omidyar Network and CommerceNet. It has more than 8,000 members signed up for its various Web sites. Memberships to the sites are free.

A Healthy Revenue Model

Waterfront Media, on the other hand, has an aggressive advertising approach with a much wider editorial scope more akin to WebMD. Its EverdayHealth.com site, which focuses on diet and fitness and skews toward women, ranks second in audience size with 12.1 million unique visitors in December, tripling from a year ago when the site had 2.7 million unique visitors, according to comScore. The site provides general-interest health information, tips from specialists, health news and even healthy recipes.

Waterfront Media's Web properties also include a site for Arthur Agatston's South Beach Diet, Denise Austin's fitness programs, the "What to Expect When You're Expecting" brand and Dr. Andrew Weil's health plans, among others. To differentiate its sites from others, Waterfront Media seeks to create a brand message specific from other sites, particularly WebMD.

"I think what EverydayHealth is about is helping consumers manage their health on a day-to-day basis, so it's not as encyclopedic," said Waterfront Media Chief Executive Benjamin Wolin.

Waterfront Media currently gets about 65% of its revenue through advertising and the remaining 35% through membership fees. The company, which reached profitability in 2007, is planning to be cash flow positive around the middle of this year, Wolin said, though he declined to comment on specific revenue. The average membership fee is about $20.

Waterfront Media's advertising rates vary, Wolin said. The rates, measured in cost per thousand impressions, range from $20 to $40 and can be as high as $100. In addition, Waterfront Media also sells sponsorships, which allow a company to target its reach to a certain kind of audience across the site. In total, one company can spend $500,000 to $2 million in deals with Waterfront, Wolin said.

Waterfront Media first started out with a subscription model in 2002, the same year the company was founded, and then adjusted to emphasize advertising in 2005. The shift of advertising from television to the Web is key to the growth all of these companies. Health care Web sites are popular with pharmaceutical companies, which can place ads for a fraction of the cost of the additional time on TV or space in print needed to disclose risks and side effects.

But even with a flurry of new competition, WebMD shows no signs of weakness. Recent analyst reports from both Citigroup and Bank of America give the company a positive rating, considering factors such as advertising demand and a content sharing deal with Yahoo Inc. The company currently has a 33% year over year organic revenue growth in advertising and sponsorships, according to Citigroup.

Despite the challenges, however, the strong market seems to have room for the new players. "There's a real simple bullish growth sector there," said Citigroup's Mahaney.