<PAGE>   1
                     U.S. SECURITIES & EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                  FORM 10-QSB

( X ) Amended Quarterly report under Section 13 or 15(d) of the Securities
Exchange Act of 1934 for the quarter period of December 31, 1996.

(   ) Transition report under Section 13 or 15(d) of the Securities Exchange
Act of 1934 for the transition period from              to              .

                         Commission File Number 0-9185

                            MEDCO HEALTH CORPORATION
                      (Formerly Williston Oil Corporation)

Nevada                                                             22-1934084
(State or other jurisdiction of           (IRS Employer Identification Number)
incorporation or organization)

532 Sylvan Avenue
Englewood Cliffs, New Jersey                                            07632
(address of Principal Executive Offices)                           (Zip Code)

                                 (201)541-8444
              (Registrant's telephone number, including area code)

         Securities registered under Section 12(b) of the Exchange Act:

                                      None

         Securities registered under Section 12(g) of the Exchange Act:

                     Class A Common Stock, $.001 Par Value

     Check whether the issuer (1) filed all reports required to be filed by
Section 13 or 15(d) of the Exchange Act during the preceding twelve (12) months
(or for such shorter period that registrant was required to file such
reports), and (2) has been subject to such filing requirements for the past
ninety (90) days. YES ( X )(   ).

                      Applicable Only to Corporate Issuers

     State the number of shares outstanding of each of the issuer's classes of
     common equity:

     36,695,543 Shares of Class A Common Stock, $.001 par value
      1,250,000 Shares of Class B Common Stock, $.001 par value  

                 Transitional Small Business Disclosure Format

                               YES ( X ) NO ( X )
<PAGE>   2
Item 1. Financial Statements

     The financial statements of the company, required to be included in this
report pursuant to Item 310(a) of Regulation S-13, are set forth below:
<PAGE>   3
                Medco Health Corporation (formerly Medco, Inc.)
                         (A Development Stage Company)
                                        
                                        
                            Statements of Operations


<TABLE>
<CAPTION>
                                                                                                                 Cumulative
                                                       Three months                   Six months                Period from
                                                          ended                         ended                  July 1, 1994
                                                       December 31,                  December 31,               (Date of
                                                -----------------------------   --------------------------     Inception) to
                                                   1995           1996            1995            1996        December 31, 1996
                                                -------------    ------------    ----------      ----------   -----------------

<S>                                             <C>             <C>             <C>             <C>             <C>
Revenues                                        $    --         $    --         $    --         $    --         $ 83,069

Cost of sales                                       179              --              --              --           16,939
                                                -------         -------         -------         -------         --------

Gross profit                                       (179)             --              --              --           66,130
                                                -------         -------         -------         -------         --------


General and administrative expenses:
  Payroll -- officers                                --              --              --          32,390           39,890           
  Payroll -- other                                   --              --              --           8,000           23,689
  Taxes and licenses                                146           1,564             246           4,082            6,382
  Management fees                                    --           2,850              --           3,915            9,840 
  Commission expense                              6,737              --          13,871             200            8,600
  Travel                                             --              --              --             450            7,324
  Miscellaneous                                      --             354             750           1,995            2,745
  Bad debt                                           --              --              --              --           60,746
  Insurance                                          --           5,389             605           8,169           13,457
  Supplies                                           --             200             230           2,470            2,470
  Advertising                                       370              --             396              --            1,844
  Truck and auto expenses                           124             124             360             870            4,372
  Rent                                            1,500           8,750           3,000          11,000           22,075
  Telephone                                         340             528           1,579             606            7,419
  Utilities                                         225             300             414             434            2,559
  Repairs and maintenance                            --              --             138              35              987
  Office expense                                     98              25             497             219            1,887
  Seminars                                           68              --              68              --              648
  Professional fees                                  --              --           1,000           4,045           11,718
  Depreciation and amortization                   2,627           2,650           5,254           5,300           19,134
                                                -------         -------         -------         -------         --------
                                                 12,235          22,734          28,408          84,180          247,786
                                                -------         -------         -------         -------         --------
</TABLE>


                       See Notes to Financial Statements
<PAGE>   4
                Medco Health Corporation (formerly Medco, Inc.)
                         (A Development Stage Company)
                                        
                                        
                            Statements of Operations


<TABLE>


<S>                                             <C>             <C>             <C>             <C>             <C>
Operating loss                                   (12,414)        (22,734)        (26,510)        (84,180)        (181,656)

Gain (loss) on equipment                              --              --              --          59,800           26,172
                                                ---------       ----------      ----------      ---------       ----------
Loss before provision for income taxes           (12,414)        (22,734)        (26,510)        (24,380)        (155,484)

Provision for income taxes                            --              --              --              --              827
                                                ---------       ----------      ----------      ---------       ----------

Net loss                                        $(12,414)       $(22,734)       $(26,510)       $(24,380)       $(156,311)
                                                =========       =========       =========       =========       ==========

Net loss per common share                       $     --        $     --        $     --        $      --       $      --
                                                =========       =========       =========       =========       ==========

</TABLE>




                       See Notes to Financial Statements
<PAGE>   5
                Item 2. Management's Discussion and Analysis of
                  Financial Condition and Result of Operations

        The following is management's discussion and analysis of significant
factors which have affected the Registrant's financial position and operations
during the fiscal quarter that ended December 31, 1996. 

                        Liquidity and Capital Resources

        The activities of the registrant since its reorganization on January
16, 1996 have been financed by various loans.

        The company currently owns three vehicles, a Land Cruiser, a BMW, and a
Dodge Colt. The company will also own the laboratory, including all of its
furnishings, once it is complete.

        The company currently had a negative net worth. There is no assurance
that the company will, in fact, be able to raise adequate funding and actually
expand its operations as contemplated, or even to bring its present operations
to a profitable level.

                             Results of Operations

        The company's revenues from its date of inception until December 31,
1996 is $83,069.00. However, the company had no revenue for the three months
that ended December 31, 1996.

        The management of the company has continued to devote the company's
resources to the completion of the clinical laboratory in Engelwood Cliffs, New
Jersey.

                    Item 6. Exhibits and Reports on Form S-K

        (a) Exhibits filed herewith:

        None

        (b) Current reports on Form 10KSB; dated April 17, 1997, filed with the
Securities and Exchange Commission.
<PAGE>   6
                                   SIGNATURES

        In accordance with the requirements of the Exchange Act, the registrant
caused this report to be signed on its behalf by the undersigned thereunto duly
authorized.

                                        MEDCO HEALTH CORPORATION




                                        By: /s/ FAHIM SAHRAIE       
                                           ----------------------------
                                           FAHIM SAHRAIE
                                           President/Director




                                        By: /s/ HASHEM SAHRAIE
                                           ---------------------------
                                           HASHEM SAHRAIE
                                           Secretary/Director