Filed by: Medical Manager Corporation
                                    This communication is filed pursuant to
                                    Rules 165 and 425 promulgated under the
                                    Securities Act of 1933, as amended.
                                    Subject Company: Medical Manager Corporation
                                    Commission File Number: 000-17822


Investors are urged to read the various filings of Medical Manager Corporation,
CareInsite, Inc. and Healtheon/WebMD Corporation that have been filed and will
be filed with the Securities and Exchange Commission with respect to the pending
acquisitions of Medical Manager and CareInsite by Healtheon/WebMD, including the
proxy statement/registration statement that is required to be filed with respect
to the pending acquisitions. The Securities and Exchange Commission filings are
available to the public at the Securities and Exchange Commission's web site at
http://www.sec.gov. Investors can also obtain free copies of the documents
relating to Medical Manager by contacting the Medical Manager Investor Relations
department at Medical Manager Corporation, 669 River Drive, Center 2, Elmwood
Park, New Jersey 07407, (201) 703-3400, http://www.medicalmanager.com

         SET FORTH BELOW IS A JOINT PRESS RELEASE ISSUED ON MAY 31, 2000 BY
MEDICAL MANAGER, CAREINSITE AND HEALTHEON/WebMD. Other than historical
information set forth therein, the press release set forth below contains
forward-looking statements that involve risks and uncertainties, including those
relating to the ability of Healthon/WebMD, Medical Manager and CareInsite's
services to improve healthcare, decrease clinical and administrative costs and
inefficiencies and accelerate physician adoption. Actual results could be
materially different from those discussed in the press release set forth below.
Factors that could cause actual results to differ include, among others: the
companies' limited operating histories, continued growth in the use of the
Internet, and acceptance of the Internet as a secure medium over which to
conduct transactions. Additional risks associated with the companies' businesses
can be found in the companies' periodic filings with the SEC.




Healtheon/WebMD, Medical Manager, and
CareInsite Receive Requests For
Additional Information on Proposed Agreement

ATLANTA and ELMWOOD PARK, N.J., May 31 /PRNewswire/ -- Healtheon/WebMD Corp.
(Nasdaq: HLTH - news), Medical Manager Corporation (Nasdaq: MMGR - news), and
its publicly traded subsidiary, CareInsite Inc. (Nasdaq: CARI - news) today
announced that they had each received a regulatory request for additional
information in connection with their application for Hart-Scott-Rodino clearance
of the proposed agreement for Healtheon/WebMD to acquire Medical Manager and
CareInsite, which was announced on February 14, 2000.

The requests extend the waiting period for Hart-Scott-Rodino clearance, during
which Healtheon/WebMD, Medical Manager, and CareInsite cannot close the
transaction, until 20 days following substantial compliance by the parties with
the regulatory request.

About Healtheon/WebMD

Healtheon/WebMD is the first end-to-end, Internet healthcare company connecting
physicians and consumers to the entire healthcare industry. Healtheon/WebMD is
using the Internet to facilitate a new system for the delivery of healthcare,
resulting in a single, secure environment for all communications and
transactions that will enable a more efficient and cost effective healthcare
system. Healtheon/WebMD has its corporate headquarters in Atlanta, GA and its
technology headquarters in Santa Clara, CA. For more information visit
http://www.webmd.com .

About Medical Manager Corporation

Medical Manager Corporation operates three lines of business. Medical Manager
Health Systems is a leading provider of physician practice management systems.
Porex Corporation is a leader in the development, manufacturing and distribution
of porous and solid plastic products. CareInsite, Inc. provides innovative
healthcare network and clinical communications services that leverage Internet
technology to enable the confidential exchange of clinical, administrative and
financial information among physicians and their patients, and affiliated health
plans, providers and suppliers.

About CareInsite, Inc.

CareInsite, Inc. provides innovative healthcare network and clinical
communications services that leverage Internet technology to enable the
confidential exchange of clinical, administrative and financial




information among physicians and their patients, and affiliated health plans,
providers and suppliers. The Company's services are designed to improve the
quality of patient care and reduce the administrative and clinical costs of
healthcare. CareInsite is a 68% owned subsidiary of Medical Manager Corporation.