BOSTON – Partners HealthCare, whose affiliate physicians write 3.6 million prescriptions a year on paper or faxes, is poised for a system-wide rollout of an electronic prescribing system that it built in-house.

Boston-based Partners, an integrated health system founded by Brigham and Women’s Hospital and Massachusetts General Hospital, also operates several community hospitals and is a teaching affiliate of Harvard Medical School.

It works with an electronic medical record system that was also built in-house, It’s called LMR – Longitudinal Medical Records – and it is Partners’ outpatient record.

A small e-prescribing pilot was scheduled to begin at the end of April with just a handful of physicians. Plans were to follow the initial pilot with another beginning June 1 with 125 users – three practices.

“Assuming the pilot will not reveal major issues – software routing, user training, patient satisfaction, pharmacy issues, etc…– we should be able to rapidly ramp it up to the rest of the LMR user base, said Carol Broverman, the Partners senior corporate manager who is heading up the project. “Decisions will be made based on the outcome of the pilot,” she said.

Broverman describes Partners as a “fast follower” on the healthcare IT front – abreast of development, but not too far ahead. Partners usually chooses to design and build the technology in-house because often users ask for functionality not yet available from commercial products, Broverman said.

Partners’ LMR has more than 20,000 users, of which about 12,000 Broverman describes as “active” daily users. At full rollout of the e-prescribing system, she said, about 5,000 prescribing physicians will use it.

“Benefits are both patient safety and in saving costs for faxing,” she said.

More than 8.8 million adverse drug events occur each year in ambulatory care, according to the Center for Information Technology and Leadership, and an estimated 3 million are preventable.

“Electronic prescribing improves efficiencies while helping to eliminate potentially harmful drug interactions and other medication problems,” HHS Secretary Michael Leavitt said last month when he reported to Congress on the state of Medicare electronic prescribing projects. “It also solves the problem of hard-to-read handwritten prescriptions.”

On the cost savings front for Partners, a conservative estimate – based on one million faxed prescriptions a year – would result in $50,000 in savings a year, Partners estimates.

At the start, the Partners project will enable the electronic transmission of prescriptions. The physicians will not have to change what they do today, Broverman said.  “They won’t see any difference.” The transmission to the pharmacies occurs behind the scenes.

By next year, Partners expects physicians will be able to get patients medication history via e-prescribing and also perhaps better handle pharmacy-initiated refills, eliminating the need for numerous phone calls among patients, doctors and pharmacies.

Eventually, Broverner said, Partners expects physicians will be able to see formularies for a given insurer.

“The biggest thing,” said Broverman, is it really puts us on the road to functionality that will get us on the road to data-sharing.”

Partners’ physicians will be registered to do e-prescribing via the MA-SHARE RxGateway. MA-SHARE is Massachusetts’ regional health information organization, RHIO.

Massachusetts this year attained No. 1 ranking for its e-prescribing efforts statewide. The Safe-Rx Award the state received is based on an analysis of data from new prescriptions and refill responses electronically transmitted over the Pharmacy Health Information Exchange, operated by SureScripts.