Company Press Release

Medical Manager to Acquire Physician Computer Network

ELMWOOD PARK, NJ/MORRIS PLAINS,  NJ--(BUSINESS WIRE)--Dec. 7, 1999--Medical
Manager Corporation  (NASDAQ:  MMGR) and Physician Computer Network,  Inc. (OTC:
PCNI) announced today that the two companies have signed a definitive  agreement
which provides for Medical Manager to acquire substantially all of the operating
assets of Physician  Computer Network,  one of the nation's largest providers of
physician practice management systems, for a purchase price of $53 million, plus
the assumption of certain liabilities.

Medical Manager Corporation is the nation's leading provider of physician office
practice  management   systems.   Medical  Manager   Corporation,   through  its
subsidiaries,  Medical Manager Health Systems and Careinsite (NASDAQ:  CARI), is
transforming the information  infrastructure of America's practicing  physicians
and with the  acquisition  of Physician  Computer  Network (PCN) will no provide
practice  management systems to over 185,000 physicians  throughout the U.S. The
acquisition  of PCN  represents  another  stepping  stone  toward  its  goal  of
revolutionizing the way in which physicians can communicate  electronically with
the nation's health plans,  pharmacies,  labs,  other providers and suppliers of
healthcare, and their patients.

PCN also announced today that it has voluntarily  filed a petition under Chapter
11 of the U.S.  Bankruptcy Code and a Plan of  Reorganization  that provides for
the sale of the assets to Medical Manager upon confirmation of the Plan. Medical
Manager will  exchange  $15.5 million in cash and $37.5 million in shares of its
common stock and assume certain liabilities in exchange for substantially all of
the operating assets of PCN and its subsidiaries. Completion of the acquisition,
which is expected in the Spring of 2000 is subject to  confirmation  of the Plan
of  Reorganization  and certain other customary  conditions to closing.  Medical
Manager  has also  agreed  to  provide  debtor-in-possession  financing  to PCN,
subject to court approval.

The integration of PCN into the Medical Manager  franchise  creates  significant
opportunities for the combined  organization.  Medical Manager's  penetration in
key geographic markets provides  opportunities for more comprehensive as well as
more  efficient  customer  support.  It also creates  significant  cross-selling
opportunities between the two organizations. Commenting on the acquisition, John
Kang,  Co-CEO of Medical  Manager,  said,  "With more than 55,000  providers  in
approximately  8,000  sites,  PCN's  installed  base and  national  distribution
network increases Medical Manager Health System's strong presence on physicians'
desktops and creates an unparalleled  sales,  service and support  organization.
Increasing the size of Medical Manager's  franchise  enhances the value to other
potential  business  partners  interested in gaining a more efficient channel of
physician distribution."

In conjunction  with the signing of the acquisition  agreement,  Medical Manager
and PCN have extended their previously announced exclusive  arrangement to offer
Careinsite's   web-based  physician  portal  services  and  clinical  e-commerce
transactions to PCN's entire client base. Careinsite, through its agreement with
Medical Manager,  will be the exclusive  provider of a fully integrated suite of
transaction services to approximately forty percent of all ambulatory care

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physicians across the U.S.

Martin J. Wygod,  Chairman of Medical Manager,  said, "The acquisition of PCN by
Medical  Manager  creates   significant   opportunities  for  Careinsite.   This
acquisition  strengthens  Careinsite's appeal to large health plans,  pharmacies
and  clinical  labs  given  the  combined   physician   base  and   distribution
organizations located in virtually every local geographic market in the country.
It also  accelerates  Careinsite's  ability to offer secure  web-based  services
which are fully  integrated  into the workflow and data of PCN's installed base.
In addition to aggregating large numbers of physicians,  Careinsite continues to
focus on  strategic  partnerships  which will  enhance  its goal of  creating an
all-payer, all-patient network."

Carter Evans,  President of PCN,  said,  "Medical  Manager has been an excellent
competitor  of ours for over fifteen years and I am pleased to announce that PCN
will join such a strong and reputable  organization.  Leveraging PCN's installed
base over Medical Manager's  infrastructure  will enable PCN to regain financial
health.  Joining the Medical  Manager  team and fully  integrating  Careinsite's
services  into  PCN's   products  will  ensure  that  PCN's   customers  have  a
market-leading product and superior customer service and support."

Medical Manager Corporation  (NASDAQ:  MMGR) operates three principal lines of
business:  physician  practice  management  systems  through  Medical Manager
Health Systems,  Inc., healthcare  e-commerce through Careinsite,  Inc. (NASDAQ:
CARI), and plastics and filtration technologies through Porex Corporation.

The  statements  contained  in  this  release,  other  than  the  terms  of  the
acquisition, are forward looking statements that involve risks and uncertainties
including, but not limited to, the successful closure of the acquisition and the
integration of the Medical Manager and Physician  Computer  Network  businesses,
the  feasibility of developing  commercially  profitable  healthcare  e-commerce
services,   the  effect  of  economic  conditions,   physician  and  other  user
acceptance,  the impact of competitive products,  services and pricing,  product
development,  commercialization and technological difficulties,  and other risks
detailed in Medical Manager's and Physician  Computer  Network's  Securities and
Exchange Commission filings.


Contact:

         Medical Manager Corporation
         James R. Love
         Executive Vice President and
         Chief Financial Officer
         201/703-3400
                  or
         Physician Computer Network
         Carter Evans
         President
         973/490-3100

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