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                                                                    EXHIBIT 10.3


                           KING PHARMACEUTICALS, INC.


                                FOURTH AMENDMENT
                                ----------------
                          dated as of October 24, 2000

                                     to the

                      AMENDED AND RESTATED CREDIT AGREEMENT
                      -------------------------------------
                          dated as of December 22, 1998
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                           FOURTH AMENDMENT dated as of October 24, 2000 (this
                   "Amendment"), to the Amended and Restated Credit Agreement
                   (the "Credit Agreement") dated as of February 27, 1998, as
                   amended and restated as of December 22, 1998, as further
                   amended pursuant to a Second Amendment dated as of July 7,
                   2000 and a Third Amendment dated as of September 28, 2000,
                   among KING PHARMACEUTICALS, INC., a Tennessee corporation
                   (the "Borrower"); the lenders party thereto (the "Lenders");
                   and CREDIT SUISSE FIRST BOSTON, a bank organized under the
                   laws of Switzerland, acting through its New York Branch as
                   administrative agent (in such capacity, the "Administrative
                   Agent"), as collateral agent (in such capacity, the
                   "Collateral Agent") and as swingline lender (in such
                   capacity, the "Swingline Lender") for the Lenders; First
                   Union National Bank, as issuing bank (in such capacity, the
                   "Issuing Bank") for the Lenders; and First Union National
                   Bank and NationsBank, N.A., as syndication agents (in such
                   capacity, the "Syndication Agents" and, together with the
                   Administrative Agent and the Collateral Agent, the "Agents")
                   for the Lenders.

         The Borrower has requested that the Lenders amend certain provisions of
the Credit Agreement to permit the Borrower to (i) eliminate the requirement
that certain repayments of Revolving Loans (such term and each other capitalized
term used and not otherwise defined herein having the meaning assigned to it in
Section 1.01 of the Credit Agreement as amended hereby) result in a commensurate
reduction of the Revolving Credit Commitments and (ii) repurchase or redeem up
to $60,000,000 aggregate principal amount of its 10-3/4% Senior Subordinated
Notes due 2009. The Lenders are willing so to amend the Credit Agreement on the
terms and subject to the conditions set forth herein.

         Accordingly, in consideration of the mutual agreements herein contained
and other good and valuable consideration, the sufficiency and receipt of which
are hereby acknowledged, the parties hereto agree as follows:

         SECTION 1. Amendment of Credit Agreement. The Credit Agreement is
hereby amended, effective as of the Amendment Effective Date, as follows:

         (a) Amendment of Section 2.09(c). Section 2.09(c) of the Credit
Agreement is hereby amended by adding the following proviso at the end of such
Section:

                  "; provided that no reductions in the Revolving Credit
                  Commitments shall be required pursuant to this Section 2.09(c)
                  as a result of any such prepayment or cash collateralization
                  made on or after October 24, 2000."

         (b) Amendments to Section 6.15. Clause (a) of Section 6.15 of the
Credit Agreement is hereby amended as follows:

                  (i) The word "and" immediately preceding clause (B) is deleted
                  and replaced with a comma.
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                   (ii) The word "or" immediately following the words
                   "Additional Securities" is deleted and replaced with the
                   phrase ", (C) the repurchase or redemption of up to
                   $60,000,000 aggregate principal amount of the Borrower's
                   10-3/4% Senior Subordinated Notes Due 2009 or (D) ".

         SECTION 2. Representations and Warranties. To induce the other parties
hereto to enter into this Amendment, the Borrower represents and warrants to
each of the Lenders, the Administrative Agent and the Collateral Agent that, as
of the Amendment Effective Date:

         (a) The representations and warranties set forth in Article III of the
Credit Agreement are true and correct in all material respects on and as of the
Amendment Effective Date with the same effect as though made on and as of the
Amendment Effective Date, except to the extent such representations and
warranties expressly relate to an earlier date.

         (b) After giving effect to the agreements and waivers herein, no
Default or Event of Default has occurred and is continuing.

         SECTION 3. Effectiveness. This Amendment shall become effective on the
date (the "Amendment Effective Date") that the Administrative Agent shall have
received counterparts of this Amendment that, when taken together, bear the
signatures of the Borrower and the Required Lenders.

         SECTION 4. Effect of Amendment. Except as expressly set forth herein,
this Amendment shall not by implication or otherwise limit, impair, constitute a
waiver of or otherwise affect the rights and remedies of the Lenders, the
Administrative Agent or the Collateral Agent under the Credit Agreement or any
other Loan Document, and shall not alter, modify, amend or in any way affect any
of the terms, conditions, obligations, covenants or agreements contained in the
Credit Agreement or any other provision of the Credit Agreement or any other
Loan Document, all of which are ratified and affirmed in all respects and shall
continue in full force and effect. Nothing herein shall be deemed to entitle the
Borrower to a consent to, or a waiver, amendment, modification or other change
of, any of the terms, conditions, obligations, covenants or agreements contained
in the Credit Agreement or any other Loan Document in similar or different
circumstances. This Amendment shall apply and be effective only with respect to
the provisions of the Credit Agreement specifically referred to herein.

         SECTION 5. Counterparts. This Amendment may be executed in any number
of counterparts and by different parties hereto in separate counterparts, each
of which when so executed and delivered shall be deemed an original, but all
such counterparts together shall constitute but one and the same instrument.
Delivery of any executed counterpart of a signature page of this Amendment by
facsimile transmission shall be as effective as delivery of a manually executed
counterpart hereof.
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         SECTION 6. Applicable Law. THIS AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

         SECTION 7. Headings. The headings of this Amendment are for purposes of
reference only and shall not limit or otherwise affect the meaning hereof.
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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed by their duly authorized officers, all as of the date and year
first above written.

                                      KING PHARMACEUTICALS, INC.


                                      By:      /s/ John M. Gregory
                                               --------------------------------
                                               Name:  John M. Gregory
                                               Title:  Chairman & CEO


                                      CREDIT SUISSE FIRST BOSTON,
                                      individually and as Administrative Agent,
                                      Collateral Agent and Swingline Lender,


                                      By:      /s/ Robert N. Finney
                                               --------------------------------
                                               Name:  Robert N. Finney
                                               Title:  Managing Director

                                      By:      /s/ Vitaly G. Butenko
                                               --------------------------------
                                               Name:  Vitaly G. Butenko
                                               Title:  Asst. Vice President


                                      AMSOUTH BANK


                                      By:      /s/ Jerry C. Greene
                                               --------------------------------
                                               Name:  Jerry C. Greene
                                               Title:  Senior Vice President


                                      BANK OF AMERICA, N.A.


                                      By:      /s/ Joseph L. Corah
                                               --------------------------------
                                               Name:  Joseph L. Corah
                                               Title:  Principal
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                                      BANK POLSKA KASA OPIEKI SA


                                      By:      /s/ Harvey Winter
                                               --------------------------------
                                               Name:  Harvey Winter
                                               Title:  Vice President


                                      FIRST TENNESSEE BANK


                                      By:      /s/ David L. Wagner
                                               --------------------------------
                                               Name:  David L. Wagner
                                               Title:  Community Bank President


                                      FIRST UNION NATIONAL BANK


                                      By:      /s/ Ann M. Dodd
                                               --------------------------------
                                               Name:  Ann M. Dodd
                                               Title:  Senior Vice President


                                      FLEET NATIONAL BANK


                                      By:      /s/ Lori H. Jou
                                               --------------------------------
                                               Name:  Lori H. Jou
                                               Title:  Vice President


                                      NATIONAL BANK OF CANADA


                                      By:      /s/ Jundie Cadiena
                                               --------------------------------
                                               Name:  Jundie Cadiena
                                               Title:  Assistant Vice President

                                      By:      /s/ Alex M. Council IV
                                               --------------------------------
                                               Name:  Alex M. Council IV
                                               Title:  Vice President
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                                      UNION BANK OF CALIFORNIA, N.A.


                                      By:      /s/ Richard P. Degrey
                                               --------------------------------
                                               Name:  Richard P. Degrey
                                               Title:  Vice President