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                                                                  EXHIBIT 10.18a

                          AMENDMENT TO LEASE AGREEMENT


         AMENDMENT date February 26, 2002, between Forsyth Centre Associates,
L.L.C. ("Landlord") and D&K Healthcare Resources, Inc. ("Tenant").



                                    RECITALS


     A.  Landlord and Tenant entered into and executed that certain Lease
         Agreement dated October 10, 2001 (the "Lease");

     B.  Pursuant to the Lease, the "Lease Premises" consist of the entire tenth
         floor of the Building, a portion of the ninth floor of the Building and
         a portion of the third flo0r of the Building; the third floor space, as
         outlined on Exhibit 1.1A, is not sufficient for Tenant's needs and
         Tenant wishes to lease additional space on the fifth floor of the
         Building in lieu of the space of the third floor.


                                    AGREEMENT


     In consideration of the foregoing, the mutual covenants herein contained
and other good and valuable consideration (the receipt, adequacy and sufficiency
of which are hereby acknowledged by the parties by their execution hereof), the
parties agree as follows:

     1.  Defined Terms. Unless otherwise defined herein, all capitalized terms
         used in this Amendment have the meanings ascribed to them in the Lease.

     2.  Leased Properties. The definition of Leased Properties is amended to
         provide that Landlord demises and leases to Tenant, and Tenant leases
         and rents from Landlord, a portion of the fifth floor of the Building
         consisting of approximately 4,086 rentable square feet; the fifth floor
         space is in lieu of the third floor space and in addition to the entire
         tenth floor and a portion of the ninth floor of the Building. The fifth
         floor space is outlined on Exhibit 1.1A attached hereto which exhibit
         shall replace and become the new Exhibit 1.1A to the Lease. The actual
         rentable square feet shall be determined after completion of
         construction of the Lease Premises and shall be determined according to
         ANSI/BOMA Z65.1-1996.

     3.  No Other Modifications. Nothing herein contained in any way impairs the
         Lease, or alters, waives, annuls, varies or affects any provisions,
         condition or




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         covenant therein, except as specifically set forth in this Amendment.
         All other provisions of the Lease remain in full force and effect.

4.       Further Assurances. The parties will execute and deliver such further
         instruments and do such further acts and things as may be required to
         carry out the intent and purpose of this Amendment.

5.       Amendments. This Amendment may be amended, modified or supplemented
         only by written agreement of the parties hereto.





                                         "LANDLORD"
                                         FORSYTH  CENTRE  ASSOCIATES, L.L.C.

                                         By    /s/  John L. Hank
                                               ------------------



                                         `TENANT'
                                         D&K HEALTHCARE RESOURCES, INC.

                                         By     /s/   Martin D. Wilson
                                               ------------------------