<PAGE> 1

               EIGHTH AMENDMENT TO FOURTH AMENDED AND RESTATED
                         LOAN AND SECURITY AGREEMENT
                         ---------------------------

    THIS EIGHTH AMENDMENT TO THE FOURTH AMENDED AND RESTATED LOAN AND
SECURITY AGREEMENT (this "Amendment") is made as of June 30, 2000, by and
                          ---------
among FLEET CAPITAL CORPORATION, a Rhode Island corporation (the "Lender"),
                                                                  ------
and D&K HEALTHCARE RESOURCES, INC. ("D & K"), JARON, INC. ("Jaron") and
                                     -----                  -----
JEWETT DRUG CO., a South Dakota corporation ("Jewett") (D & K, Jaron and
                                              ------
Jewett are sometimes hereinafter referred to individually as "Borrower" and
                                                              --------
collectively as "Borrowers").
                 ---------

                            Preliminary Statements
                            ----------------------

    C. Lender, and Borrowers are parties to that certain Fourth Amended and
Restated Loan and Security Agreement dated as of August 7, 1998 (as amended,
restated or renewed from time to time, the "Loan Agreement"). Capitalized
                                            --------------
terms used herein and not otherwise defined shall have the meanings given
them in the Loan Agreement.

    D. D & K has requested that Lender amend certain provisions of the Loan
Agreement to decrease the Capital Base the Borrowers must maintain during the
specific period between June 30, 2000 and September 30, 2000.

    NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties agree as follows:

    1.   Financial Covenants.  Section 8.3(C) of the Loan Agreement [relating
         -------------------
         to Specific Financial Covenants] is hereby deleted in its entirety
         and replaced with the following new Section 8.3(C):

              (C) Maintenance of Capital Base.  Maintain at all times during
                  ---------------------------
         the periods specified below a Capital Base in an amount not less than
         the amount shown below for the period corresponding thereto (excluding
         any purchases by D & K of its own stock made between May 20, 1999 and
         June 1, 2000 pursuant to a consent letter from Lender dated May 20,
         1999):

<TABLE>
<CAPTION>
                        Period                                      Amount
                        ------                                      ------
<S>                                                               <C>
         June 1, 1999 through December 30, 1999                   $ 1,480,000
         December 31, 1999 through June 29, 2000                  $ 3,000,000
         June 30, 2000 through September 30, 2000                 $ 7,500,000
         October 1, 2000 through June 29, 2001                    $10,000,000
         June 30, 2001 and thereafter                             $20,000,000
</TABLE>

    2.   No Claims.  Borrowers acknowledge that there are no existing claims,
         ---------
defenses (personal or otherwise) or rights of set-off or recoupment
whatsoever with respect to any of the Loan Documents.  Borrowers agree that
this Amendment in no way acts as a release or relinquishment of any Liens in
favor of the Lender securing payment of the Obligations.

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<PAGE> 2

    3.   Miscellaneous.  Except as expressly set forth herein, there are no
         -------------
agreements or understandings, written or oral, between any Borrower and
Lender relating to the Loan Agreement and the other Loan Documents that are
not fully and completely set forth herein or therein. Except to the extent
specifically waived or amended herein or in any of the documents,
instruments, or agreements delivered in connection herewith, all terms and
provisions of the Loan Agreement and the other Loan Documents are hereby
ratified and reaffirmed and shall remain in full force and effect in
accordance with the respective terms thereof. This Agreement may be executed
in one or more counterparts, and by different parties on different
counterparts. All such counterparts shall be deemed to be original documents
and together shall constitute one and the same agreement. A signature of a
party delivered by facsimile or other electronic transmission shall be deemed
to be an original signature of such party.

    IN WITNESS WHEREOF, this Amendment has been executed and delivered by the
duly authorized representatives of the parties as of the date first above
written.

                                    FLEET CAPITAL CORPORATION


                                    By: /s/ Edward M. Bartkowski
                                        --------------------------------------
                                        Name: Edward M. Bartkowski
                                        Title:  Vice President

                                    D & K HEALTHCARE RESOURCES, INC.


                                    By: /s/ Thomas S. Hilton
                                        --------------------------------------
                                        Name: Thomas S. Hilton
                                        Title: Senior Vice President and CFO

                                    JARON, INC.

                                    By: /s/ Thomas S. Hilton
                                        --------------------------------------
                                        Name: Thomas S. Hilton
                                        Title: Vice President

                                    JEWETT DRUG CO.

                                    By: /s/ Thomas S. Hilton
                                        --------------------------------------
                                        Name: Thomas S. Hilton
                                        Title: Vice President

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