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                                                                   EXHIBIT 10.28

                     THE 1999 MEDICAL MANAGER CORPORATION
                      STOCK OPTION PLAN FOR EMPLOYEES OF
                         MEDICAL MANAGER SYSTEMS, INC.


          1.   Definitions.  The terms below shall be defined as indicated.
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               1.1    Board means the Board of Directors of the Company, as
                      -----
constituted from time to time.

               1.2    Code means the Internal Revenue Code of 1986, as amended
                      ----
from time to time, or any successor statute thereto.

               1.3    Committee means the Committee of the Board described in
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Section 3.

               1.4    Common Stock means the Company's common stock, par value
                      ------------
$.01 per share.

               1.5    Company means Medical Manager Corporation, a Delaware
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corporation, and any successor corporation which adopts the Plan.

               1.6    Designated Officer means any individual who is both an
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officer and director of the Company that the Board or the Committee may
designate pursuant to Section 3 to act on their behalf with respect to the Plan.

               1.7    Exchange Act means the Securities Exchange Act of 1934, as
                      ------------
amended from time to time, or any successor statute thereto.

               1.8    Fair Market Value means, on a specified date, the last
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sales price of a Share traded on the over-the-counter market, as reported on the
National Association of Securities Dealers Automated Quotation System
("Nasdaq"), or the last closing price for a Share on the stock exchange, if any,
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on which Shares are primarily traded (or if no Shares were traded on such date,
then on the last previous date on which any Shares were so traded), or if none
of the above is applicable, the value of a Share for such date as established by
the Committee, using any reasonable method of valuation.

               1.9    Key Consultant means an individual who is a consultant,
                      --------------
agent, key contractor or other person engaged by Medical Manager, a Subsidiary
or the Company to render services to, or on behalf of, Medical Manager, a
Subsidiary or the Company.

               1.10   Key Employee means a person employed by Medical Manager, a
                      ------------
Subsidiary or the Company on a full or part time basis.
<PAGE>

               1.11   Medical Manager means Medical Manager Systems, Inc., a
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Delaware corporation and a wholly-owned subsidiary of the Company.

               1.12   Option means an option to purchase Shares granted by the
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Company pursuant to the Plan.  Options are not intended to qualify as "incentive
stock options" within the meaning of Section 422 of the Code.

               1.13   Option Agreement means a written agreement as described in
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Section 7 between the Company and the Optionee evidencing an Option.

               1.14   Option Period means the period from the date of the
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granting of an Option to the date on which that Option can no longer be
exercised.

               1.15   Option Price means the price to be paid for the Shares
                      ------------
purchased pursuant to an Option.

               1.16   Optionee means any person who is granted an Option under
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the Plan.

               1.17   Plan means the Company's 1999 Stock Option Plan for
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Employees of Medical Manager Systems, Inc., as adopted by the Board in
substantially the form set forth herein and as the same may be amended or
otherwise modified from time to time.

               1.18   Securities Act means the Securities Act of 1933, as
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amended from time to time, or any successor statute thereto.

               1.19   Shares means shares of Common Stock.
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               1.20   Subsidiary means a subsidiary of Medical Manager as
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defined under Section 424(f) of the Code.

          2.   Purpose.  The Plan is intended to encourage ownership of Common
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Stock by Key Employees and Key Consultants, upon whose judgment and interest
Medical Manager is dependent for its successful operation and growth, in order
to increase their proprietary interest in Medical Manager's and the Company's
success and to encourage them to remain in the employ of or in an independent
contractor relationship with Medical Manager, a Subsidiary or the Company, as
applicable.

          3.   Administration.
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               3.1    Board, Committee or Designated Officer.  The Plan shall be
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administered by the Board or, if the Board so determines, by a Committee
appointed by the Board from among its members (the "Committee").  The Board or
                                                    ---------
the Committee may designate one or more Designated Officers, each of whom shall
be authorized and empowered to exercise such functions and make such
determinations with respect to the Plan and the administration
<PAGE>

thereof as the Board or the Committee shall specify in the resolution
designating such officer. Any provision of the Plan to the contrary
notwithstanding, (a) in the event of any inconsistency between any action taken
by a Designated Officer and any action taken by the Committee concerning the
Plan or any Options hereunder, the action taken by the Committee shall govern,
(b) in the event of any inconsistency between any action taken by a Designated
Officer or the Committee and any action taken by the Board concerning the Plan
or any Options hereunder, the action taken by the Board shall govern and (c) no
Designated Officer may take any action except to the extent authorized to do so
by a resolution of the Board or the Committee.

               3.2    Determination of Option Terms.  Subject to the provisions
                      -----------------------------
of Sections 8 and 12, the Board, the Committee or any Designated Officer, as
applicable, shall have authority to determine the vesting and exercise schedule
with respect to Options, the persons to whom Options shall be granted, the
number of Shares to be covered by each Option, the time or times at which
Options shall be granted and the terms and provisions of the Options, and to
make all other determinations necessary or advisable for the administration of
the Plan. Options shall become exercisable as specified in the applicable Option
Agreement.

               3.3    Interpretation and Construction.  The Board, the Committee
                      -------------------------------
or any Designated Officer, as applicable, shall have the authority to interpret
and construe the provisions of the Plan or of any Option Agreement and, subject
to Section 3.1, such interpretation and construction by the Board, the Committee
or any Designated Officer shall be final and conclusive.

          4.   Eligible Persons.  The Board, the Committee or any Designated
               ----------------
Officer, as the case may be, may grant Options only to Key Employees or Key
Consultants; provided, however, that no Option shall be granted to any
individual who, at the time such Option is granted, is a director or an officer
of the Company (as defined in Rule 16a-1 promulgated under the Exchange Act).

          5.   Grant of Options.
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               5.1    Procedure.  Subject to the provisions of Sections 8.1 and
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8.2, the Board, the Committee or any Designated Officer, as applicable, may (but
shall not be required to) grant Options, provided that the person to whom the
Option is to be granted subsequently becomes a party to an Option Agreement.

               5.2    Additional Grants.  Nothing contained in the Plan shall be
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construed to preclude either the granting of an Option to an Optionee to whom
one or more Options have already been granted or the simultaneous granting of
more than one Option to the same Optionee.

               5.3    Subject to Exchange Rules.  Any and all grants of Options
                      -------------------------
shall be subject to all applicable rules and regulations of Nasdaq or any stock
exchange on which the Common Stock may then be listed.
<PAGE>

          6.   Effective Date and Expiration Date of Plan.  The Plan shall be
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effective as of the date on which the Plan is adopted by the Board (the
"Effective Date").  No Option shall be granted under the Plan after the tenth
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anniversary of the Effective Date.

          7.   Option Agreements.  Option Agreements shall be in such form as
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the Board, the Committee or any Designated Officer, as applicable, shall approve
or determine; provided, however, that all Option Agreements shall comply with
and be subject to the following terms and conditions:

               7.1    Manner, Time, and Medium of Payment.  An Option shall be
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exercised in the manner set forth in the Option Agreement relating thereto and
payment in full of the Option Price for all Shares shall be made at the time of
exercise.  Payment shall be in United States dollars in the form of cash,
certified check or bank draft, or if the Board, the Committee or any Designated
Officer so determines, by delivery of fully paid Shares, or by withholding
Shares with respect to which the Optionee has exercised such Option, having a
Fair Market Value on the date of exercise equal to the sum of the Option Price
for the withheld Shares and the remaining Shares with respect to which the
Optionee has exercised such Option, or any combination of such methods of
payment.

               7.2    Number of Shares.  Subject to Section 9, the Option
                      ----------------
Agreement shall state the number of Shares to which it pertains.

               7.3    Option Price.  The Option Price shall be determined by the
                      ------------
Board, the Committee or any Designated Officer.  Notwithstanding the foregoing,
the Option Price shall not be less than 100% of the Fair Market Value of a Share
as of the date the Option is granted.

               7.4    Option Period.  Each Option granted under the Plan shall
                      -------------
expire no later than ten years from the date the Option is granted.  Any Option
Agreement may contain provisions for the earlier expiration of the Option in the
event of the Optionee's termination of service as a Key Employee or Key
Consultant, retirement or death or in the event of a violation by an Optionee of
any of such Optionee's duties to Medical Manager, a Subsidiary or the Company.

               7.5    Date of Exercise.  An Option shall be exercisable at the
                      ----------------
times specified by the Board, the Committee or any Designated Officer, as
applicable, at the time the Option is granted; notwithstanding the foregoing, in
the event of a "Change in Control", the Board may in its sole discretion
determine that any Option granted under the Plan shall become exercisable in
full or in part, whether or not it is then exercisable.  For purposes of the
Plan, a "Change in Control" shall be deemed to have occurred:
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               (i)   when any "person", as defined in Section 3(a)(9) of the
     Exchange Act and as used in Sections 13(d) and 14(d) thereof, including a
     "group", as defined in Section 13(d) and 14(d) thereof (but excluding the
     Company and its subsidiaries, Medical Manager and its subsidiaries (and any
     successor to the Company or Medical Manager in a transaction which did not
<PAGE>

     result in a Change in Control), Martin J. Wygod and his affiliates and any
     employee benefit plan sponsored or maintained by the Company or any of its
     subsidiaries, Medical Manager or any of its subsidiaries or Martin J. Wygod
     or any of his affiliates (including any trustee of such plan acting as
     trustee)) directly or indirectly becomes the "beneficial owner" (as defined
     in Rule 13d-3 under the Exchange Act) of securities of the Company
     representing 50 percent or more of the combined power of its then
     outstanding securities with respect to the election of directors;

               (ii)  when, during any period of 24 consecutive months during the
     existence of the Plan, the individuals who, at the beginning of such
     period, constitute the Board (the "Company Incumbent Directors"), cease for
                                        ---------------------------
     any reason other than death to constitute at least a majority thereof;
     provided, however, that a director who was not a director at the beginning
     of such 24-month period shall be deemed to be a Company Incumbent Director
     if such director was elected by, or on the recommendation of or with the
     approval of at least two-thirds of the directors of the Company, who then
     qualified as Company Incumbent Directors, either actually (because they
     were directors at the beginning of such 24-month period) or by prior
     operation of this Section 7.5(ii);

               (iii) when the stockholders of the Company approve a merger or
     consolidation of the Company without the consent or approval of a majority
     of the Company Incumbent Directors;

               (iv)  when the stockholders of the Company approve a sale or
     disposition of all or substantially all of the Company's assets; or

               (v)   when the Company adopts a plan of liquidation.

In addition, the Board or the Committee, as applicable, may, in its sole
discretion, include provisions in an Option Agreement relating to a change in
control of Medical Manager or a Subsidiary.  The Board or the Committee may also
determine at the time of grant or thereafter that an Option shall become
exercisable in full or in part, whether or not it is then exercisable, upon such
circumstances or events as such Board or Committee, in its sole discretion,
merits special consideration.

               7.6    Reorganization.  In case the Company is merged or
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consolidated with another corporation, or in case of a reorganization,
separation or liquidation of the Company, the Board or the board of directors of
any corporation assuming the obligations of the Company hereunder shall make
appropriate provisions for the protection of any outstanding options by the
substitution on an equitable basis of appropriate securities of the Company, or
appropriate shares or other securities of the merged, consolidated, or otherwise
reorganized corporation, or the appropriate adjustment in the Option Price, or
both.

               7.7    Transferability; Assignability.  No Option shall be
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assignable or
<PAGE>

transferable except by will, by the laws of descent and distribution or pursuant
to a qualified domestic relations order (as such term is defined in the Code),
and no Option may be exercised other than by an Optionee or, after the death of
an Optionee, by that Optionee's personal representatives, heirs, or legatees;
provided, however, that the Committee may, subject to such terms and conditions
as the Committee shall specify, permit the transfer of an Option to an
Optionee's family members, to one or more trusts established in whole or in part
for the benefit of one or more of such family members or to any other entity
that is owned by such family members.

               7.8    Continuation of Service. No Option shall be exercisable by
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an Optionee after the earlier of: (i) the expiration of the Option Period, or
(ii) 30 days after termination of such Optionee's service as a Key Employee or a
Key Consultant or such longer period as may be determined by the Board, the
Committee or any Designated Officer, as applicable, unless such termination of
service occurs by reason of the Optionee's retirement with the consent of
Medical Manager, a Subsidiary or the Company, as the case may be, or his death.
The Board, the Committee or any Designated Officer may provide in an Option
Agreement that service with a Subsidiary or the Company shall not constitute
service as a Key Employee or a Key Consultant for purposes of such Option
Agreement. If the Optionee's services are terminated because of his retirement
with such consent or death (or if the Optionee dies within 90 days of such
retirement or within 30 days of other termination of service) the Optionee (or
the representative of the estate or the heirs or legatees of a deceased
Optionee) shall have the right to exercise the unexercised portion of the Option
which the Optionee could have exercised as of the date of his retirement or
death, provided that notice of such exercise is given to the Company in writing
before the earlier of: (i) the expiration of the Option Period, and (ii) within
90 days of the Optionee's retirement or one year of the Optionee's death, as the
case may be, or such longer period as may be determined by the Board, the
Committee or any Designated Officer. Unless otherwise provided in such
Optionee's Option Agreement, if the Optionee's service as a Key Employee or Key
Consultant is terminated because of the Optionee's violation of his duties to
Medical Manager, a Subsidiary or the Company as he may from time to time have,
the existence of which violation shall be determined by the Board, the Committee
or any Designated Officer, as applicable, in his, her or its sole discretion
(which determination shall be conclusive), all of the Optionee's Options shall
terminate immediately and the Optionee shall have no right after such
termination to exercise any Option he might have been able to exercise prior to
his termination of service.

               7.9    No Right to Continue Status. Nothing in the Plan or in any
                      ---------------------------
Option granted under the Plan shall confer (or be deemed to confer) any right on
any Optionee to continue as an employee, consultant or other service provider of
Medical Manager, any Subsidiary or the Company or shall interfere in any way
with the right of Medical Manager, any Subsidiary or the Company to terminate
such status at any time, with or without cause and with or without notice.

               7.10   Rights as a Stockholder.  An Optionee shall have no rights
                      -----------------------
as a stockholder with respect to Shares covered by any Option until the date the
Company has issued or delivered such Shares to the Optionee, and the Optionee's
name shall have been entered as the
<PAGE>

stockholder of record on the books of the Company and then only as to such
Shares as are actually issued and delivered to the Optionee.

               7.11   Other Provisions.  Option Agreements shall contain such
                      ----------------
other terms and conditions not inconsistent with the Plan as the Board, the
Committee or any Designated Officer, as applicable, shall deem advisable.

               7.12   Compliance with Law.  Notwithstanding any provision of the
                      -------------------
Plan or any Option Agreement to the contrary, no Option may be granted or
exercised at any time when such Option or the granting or exercise thereof or
payment therefor may result in the violation of any law or governmental order or
regulation.

               7.13   Securities Laws.  The Company may require each Optionee to
                      ---------------
represent to the Company, in writing, when an Option is exercised that such
Optionee is exercising such Option for his own account for investment only, and
not with a view to distribution, and that the Optionee will not make any sale,
transfer, or other disposition of any Shares so purchased except (i) pursuant to
a registration statement filed under the Securities Act, which the Securities
and Exchange Commission has declared effective, (ii) pursuant to an opinion of
counsel satisfactory in form and substance to the Company that said sale,
transfer, or other disposition may be made without registration, or (iii)
pursuant to a "no action" letter issued to the Optionee by the Securities and
Exchange Commission.  The Company may require each certificate representing
Shares purchased upon the exercise of an Option to bear a legend stating that
the Shares evidenced thereby may not be sold or transferred except in compliance
with the Securities Act and the provisions of the Plan.  No Option may be
granted or exercised at a time when such Option, or the granting or exercise
thereof, may result in the violation of any law or governmental order or
regulation.

          8.   Shares Available for Option.
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               8.1    Maximum.  Subject to Sections 7.6 and 9, no more than
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1,800,000 Shares shall be subject to purchase pursuant to Options granted under
the Plan.  At all times during the term of the Plan, the Company shall have
reserved that number of Shares less an amount equal to the number of Shares
which have been issued pursuant to the exercise of Options.  At all times after
termination of the Plan, the Company shall have reserved for issuance a number
of Shares equal to the aggregate number of Shares subject to outstanding
Options.

               8.2    Expiration or Termination. If any outstanding Option under
                      -------------------------
the Plan expires for any reason or is terminated prior to the expiration date of
the Plan as set forth in Section 6, the Shares allocable to any unexercised
portion of such Option may again be subject to an Option.

          9.   Recapitalization or Change in Par Value of Common Stock.  The
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aggregate number of Shares purchasable under Options granted and which may be
granted pursuant to the Plan and the Option Price for Shares covered by each
outstanding Option shall all be proportionately adjusted, as deemed appropriate
by the Board, the Committee or any
<PAGE>

Designated Officer if the Shares are split up, converted, exchanged,
reclassified or in any way substituted for. The Board, the Committee or such
Designated Officer shall provide for appropriate adjustments of the numbers of
shares purchasable under the Plan and of outstanding Options in the event of
stock dividends or distributions of assets or securities of other companies
owned by the Company to stockholders relating to Common Stock for which the
record date is prior to the date the Shares purchased by exercise of an Option
are issued or transferred, except that no such adjustment shall be made for
cumulative stock dividends of 10% or less (in the aggregate) or cash dividends.
Any such adjustment may include an adjustment of the Option Price or the number
of Shares for which an Option may be exercised, or may provide for an escrow of
assets or securities so distributed to be available upon future exercise. In the
event of a change in the Company's presently authorized Common Stock which is
limited to a change of all of its presently authorized Shares of Common Stock
with par value into the same number of shares without par value, or any change
of the then authorized Shares of Common Stock with par value into the same
number of shares of Common Stock with a different par value, the shares
resulting from any such change shall be deemed to be Shares as defined in
Section 1, and no change in the number of Shares covered by each Option or in
the Option Price shall take place.

          10.  Indemnification; Reliance; Exculpation.
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               10.1   Indemnification.  Each person who is or shall have been a
                      ---------------
member of the Board or of the Committee and each Designated Officer shall be
indemnified and held harmless by the Company against and from any and all loss,
cost, liability, or expense that may be imposed upon or reasonably incurred by
such person in connection with or resulting from any claim, action, suit, or
proceeding to which such person may be a party or in which such person may be
involved by reason of any action taken or failure to act under the Plan and
against and from any and all amounts paid by such person in settlement thereof
(with the Company's written approval) or paid by such person in satisfaction of
a judgment in any such action, suit, or proceeding to the fullest extent
permitted by the Delaware General Corporation Law, subject, however, to the
condition that upon the institution of any such claim, action, suit, or
proceeding, such person shall in writing give the Company an opportunity to
intervene at the Company's expense on his or her behalf.  The foregoing right of
indemnification shall not be exclusive of any other right to which such person
may be entitled as a matter of law or otherwise, or any power that the Company
may have to indemnify such person or hold him or her harmless.

               10.2   Reliance.  Each member of the Board or of the Committee,
                      --------
each Designated Officer and each other officer and employee of the Company in
performing duties under the Plan shall be entitled to rely upon information and
reports furnished in connection with the administration of this Plan by any duly
authorized officer or agent of the Company.

               10.3   Exculpation.   No member of the Board or of the Committee
                      -----------
and no Designated Officer shall be liable for any action or determination made
in good faith with respect to the Plan or any Option granted under the Plan.

          11.  Income Tax Withholding.  If Medical Manager, a Subsidiary or the
               ----------------------
Company shall be required to withhold any amounts by reason of any federal,
state or local tax
<PAGE>

rules or regulations in respect of the payment of cash or the issuance of Shares
pursuant to the exercise of an Option, Medical Manager, such Subsidiary or the
Company shall be entitled to deduct and withhold such amounts from any cash
payments to be made to the Optionee. In any event, the Optionee shall either (i)
make available to Medical Manager, such Subsidiary or the Company, promptly upon
request, sufficient funds or, if the Board, the Committee or any Designated
Officer so determines, Shares (valued at Fair Market Value as of the date the
withholding tax obligation arises (the "Tax Date")), to meet the requirements of
                                        --------
such withholding, or (ii) to the extent permitted by the Board, the Committee or
any Designated Officer, irrevocably authorize the Company to withhold from the
Shares otherwise issuable to the Optionee as a result of such exercise a number
of Shares having a Fair Market Value as of the Tax Date which alone, or when
added to funds paid or Shares delivered to Medical Manager, such Subsidiary or
the Company by the Optionee, equal the amount of the minimum withholding tax
obligation (the "Withholding Election") and Medical Manager, such Subsidiary or
                 --------------------
the Company shall be entitled to take and authorize such steps as it may deem
advisable in order to have such funds or Shares made available to Medical
Manager, such Subsidiary or the Company out of any funds or property due or to
become due to the Optionee. An Optionee's Withholding Election may only be made
prior to the Tax Date and may be disapproved by the Board, the Committee or any
Designated Officer. The Board, the Committee or any Designated Officer may
establish such rules and procedures as he, she or it may deem necessary or
advisable in connection with the withholding of taxes relating to the exercise
of any Option.

          12.  Amendment or Termination of Plan.  The Board or the Committee may
               --------------------------------
modify, amend or terminate the Plan in whole or in part at any time; provided,
however, that (i) no modification or amendment shall be effective without
stockholder approval if such approval is required by law or under the rules of
Nasdaq or of the stock exchange on which the Shares are listed and (ii) no such
termination, modification, or amendment of the Plan shall adversely alter or
affect the terms of any then outstanding Options previously granted hereunder
without the consent of the Optionee.

          13.  Set-Off.  If at any time an Optionee is indebted to Medical
               -------
Manager, any Subsidiary or the Company, the Company may in the discretion of the
Board, the Committee or any Designated Officer (a) withhold from the Optionee
(i) following the exercise by the Optionee of an Option, Shares issuable to the
Optionee having a Fair Market Value on the date of exercise up to the amount of
such indebtedness or (ii) following the sale by an Optionee of Shares received
pursuant to the exercise of an Option, amounts due to an Optionee in connection
with the sale of such Shares up to the amount of such indebtedness, or (b) take
any substantially similar action.  The Board, the Committee or any Designated
Officer may establish such rules and procedures as he, she or it may deem
necessary or advisable in connection with the taking of any action contemplated
by this Section 13.

          14.  Headings.  The section headings contained herein have no
               --------
substantive meaning or content and are not part of this Plan.

          15.  Governing Law.  The Plan shall be construed in accordance with
               -------------
the laws of the State of Delaware without regard to any principles of conflicts
of law.