After a months-long search, Lyft has hired a leader for its growing health care business, which helps patients get rides to non-emergency medical appointments. The company is set to announce it's hired Megan Callahan, formerly the chief strategy officer for Change Healthcare, a company that merged with McKesson in 2017, as its health lead.

The hire comes as Lyft is looking to ramp up revenues ahead of a possible IPO 2019. The company's chief business officer David Baga told CNBC by phone that health represents a "sizable chunk" of Lyft Business, which is set to achieve a annualized revenue run rate of $1 billion by the end of the year. Lyft told CNBC that the number of health care rides tripled from the third quarter of 2017 to the same period a year later.

Lyft's primary competitor, Uber, also views health as a growth opportunity. Both companies have built out dedicated teams in health, and have formulated a strategy to work with stakeholders in the industry to help patients who need help to get to the doctor's office on time.

Non-emergency medical transportation is attractive for both ride-sharing companies because insurers, including some Medicaid and Medicare plans, will often cover the cost of the ride for patients. There's a huge incentive for health plans to make transportation easier, as studies have found that a lack of transportation is a key reason why patients avoid the doctor's office.

Lyft's focus is to forge partnerships in health care with traditional players, including health systems, medical transportation brokers and health IT companies. For instance, in March it signed an exclusive deal with medical record technology provider Allscripts to make it easier for doctors to book Lyft rides for their patients.

To that end, Baga, the chief business officer, told CNBC it needed to hire an operator from the industry to maintain and build on these relationships.

"We wanted someone for the job who lives and breathes health care," he explained. "But we also wanted someone who could understand the key challenges, and be willing to break from the status quo."

Callahan told CNBC she joined Lyft because of the opportunity to improve access to health care services, particularly for low-income or elderly users.

She also said that Lyft's deep knowledge about health stood out relative to other technology players.

"I was gobsmacked by the level of understanding on HIPAA and PHI," she said, referring to the complex web of federal privacy rules and regulations that govern how health data is stored and shared. "They (Lyft) had clearly taken the time to understand the industry."

Lyft is also moving into other areas, including working with pharmaceutical companies to people get to clinical trial sites and arranging rides for physical therapists to treat patients in their homes.

Experts say that's the tip of the iceberg for Lyft and other new transportation entrants.

"There's home care, there's delivery of goods and supplies -- it becomes a market in the tens of billions of dollars if you're looking at logistics opportunities in health care," said John Brownstein, co-founder of a company in the space called Circulation Health that partners with Lyft. Circulation was recently acquired by one of the largest brokers in the space, Logisticare.

Callahan didn't rule out any of these sorts of opportunities, but said her near-term goal was to look for more ways to increase rides and reduce missed appointments.