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                     AMENDMENT NO. 7 TO BUSINESS LOAN AGREEMENT

        This Amendment No. 7 (the "Amendment") dated as of DECEMBER 31, 1999, is
between Bank of America National Trust and Savings Association (the "Bank") and
Dura Pharmaceuticals, Inc. (the "Borrower").

                                      RECITALS

        A.  The Bank and the Borrower entered into a certain Business Loan
Agreement dated as of April 14, 1997, as previously amended (the "Agreement").

        B.  The Bank and the Borrower desire to further amend the Agreement.

                                     AGREEMENT

      1  DEFINITIONS.  Capitalized terms used but not defined in this Amendment
shall have the meaning given to them in the Agreement.

      2  AMENDMENTS.  The Agreement is hereby amended as follows:
                                          
2.1 In Subparagraph 6.21(h) of the Agreement, the amount "One Hundred Fifty
Million Dollars ($150,000,000)" is substituted for the amount "One Hundred
Million Dollars ($100,000,000)."   

        3  REPRESENTATIONS AND WARRANTIES.  When the Borrower signs this
Amendment, the Borrower represents and warrants to the Bank that:  (a) there is
no event which is, or with notice or lapse of time or both would be, a default
under the Agreement except those events, if any, that have been disclosed in
writing to the Bank or waived in writing by the Bank, (b) the representations
and warranties in the Agreement are true as of the date of this Amendment as if
made on the date of this Amendment, (c) this Amendment is within the Borrower's
powers, has been duly authorized, and does not conflict with any of the
Borrower's organizational papers, and (d) this Amendment does not conflict with
any law, agreement, or obligation by which the Borrower is bound.

        4  CONDITIONS.  This Amendment will be effective when the Bank receives
the following items, in form and content acceptable to the Bank:

4.1A Two Thousand Dollar ($2,000) amendment fee due upon the execution of
this Amendment.

        5  EFFECT OF AMENDMENT.  Except as provided in this Amendment, all of
the terms and conditions of the Agreement shall remain in full force and effect.

        This Amendment is executed as of the date stated at the beginning of
this Amendment.



          BANK OF AMERICA
          NATIONAL TRUST AND SAVINGS ASSOCIATION

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          /s/ Susan J. Pepping
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          By: Susan J. Pepping, Vice President

                                      DURA PHARMACEUTICALS, INC.

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                                      /s/ Erle T. Mast
                                      -----------------------------------
                                      By:  Erle T. Mast
                                      Vice President, Finance

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                                      /s/ Mitchell R. Woodbury
                                      -----------------------------------
                                      By:  Mitchell R. Woodbury
                                      Senior V.P., General Counsel and Secretary