Document:

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                                                                   EXHIBIT 10.23

                        AMENDMENT TO EMPLOYMENT AGREEMENT

         WHEREAS, on January 1, 2000, the Company entered into certain
Employment Agreements with Mahendra G. Shah, Ph.D., R. Brent Dixon, Balaji
Venkataraman, Robert D. Godfrey, Jr. and William G. Campbell; and

         WHEREAS, the Board of Directors has resolved to further amend each
Employment Agreement, as hereinbelow more particularly set forth.

         NOW THEREFORE, each Employment Agreement between the Company and the
executive officers set forth above is hereby amended as follows:

         1.       The text of Section 7(c)(i) setting forth the definition of
"Cause" is amended to require that the executive have been convicted of the
commission of a felony or crime involving dishonesty, fraud or moral turpitude
rather than that he need just to have been charged with such a crime.

         2.       The text of Section 8(e) is amended to add that the payment of
the Salary Continuation and other benefits shall be provided following
termination of the Employment Agreement as a result of termination of the
Employment Agreement pursuant to Section 7(a)(i) as a result of the executive's
death.

         3.       Section 8(f) is amended to delete the reference to Section
7(a)(i) which provides for no Salary Continuation for other events of
termination.

         4.       A new Section 17 is added to read as follows:

                  "Any claims, disputes or controversies arising out of or
                  relating to this Agreement between the parties (other than
                  those arising under Section 11) shall be submitted to
                  arbitration by the parties. The arbitration shall be conducted
                  in Atlanta, Georgia in accordance with the rules of the
                  American Arbitration Association then in existence and the
                  following provisions: Either party may serve upon the other
                  party by guaranteed overnight delivery by a nationally
                  recognized express delivery service, written demand that the
                  dispute, specifying in detail its nature, be submitted to
                  arbitration. Within seven business days after the service of
                  such demand, each of the parties shall appoint an arbitrator
                  and serve written notice by guaranteed overnight delivery by a
                  nationally recognized express delivery service, of such
                  appointment upon the other party. The two arbitrators
                  appointed shall appoint a third arbitrator. The decision of
                  two arbitrators in writing under oath shall be final and
                  binding upon the parties. The arbitrators shall decide who is
                  to pay the expenses of the arbitration. If the two arbitrators
                  appointed fail to agree upon a third arbitrator within ten
                  days after their appointment, then an application may be made
                  by either party, upon notice to the other party, to any court
                  of competent jurisdiction for the appointment of a third
                  arbitrator, and any such appointment shall be binding upon
                  both parties."

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         5.       This Amendment shall be effective on the date approved by the
Board.

         IN WITNESS WHEREOF, the Company has caused this Amendment to be
executed on January 22, 2000.

                             FIRST HORIZON PHARMACEUTICAL CORPORATION

                             By:/s/ Mahendra G. Shah
                                -------------------------------------------
                                  Name:  Mahendra G. Shah
                                         ----------------------------------
                                  Title: Chairman and CEO
                                         ----------------------------------

                             EMPLOYEES

                             /s/ Mahendra G. Shah, Ph.D.
                             ----------------------------------------------
                             Mahendra G. Shah, Ph.D.

                             /s/ R. Brent Dixon
                             ----------------------------------------------
                             R. Brent Dixon

                             /s/ Balaji Venkataraman
                             ----------------------------------------------
                             Balaji Venkataraman

                             /s/ Robert D. Godrey
                             ----------------------------------------------
                             Robert D. Godfrey, Jr.

                             /s/ William G. Campbell
                             ----------------------------------------------
                             William G. Campbell<PAGE>   1

                                                                   EXHIBIT 10.24

                              SEPARATION AGREEMENT

         THIS SEPARATION AGREEMENT (the "Agreement") is made and entered into as
of December 22, 2000 by and between First Horizon Pharmaceuticals Corporation, a
Delaware corporation (the "Company") and Gregory P. Hauck, an individual
residing in the state of Georgia (referred to herein as "Executive").

                                  W I T N E S S E T H:

         WHEREAS, the Company and the Executive entered into an Employment
Agreement dated January 1, 2000 (the "Employment Agreement") pursuant to which
Executive has served as Vice President of Developed Products of the Company; and

         WHEREAS, Executive has determined that it is in his best interests to
resign as Vice President of Developed Products so as to allow his pursuit of
other interests; and

         WHEREAS, the Company and Executive wish to create a new understanding
as to the benefits and obligations that will be provided to and expected of
Executive following his separation from service with the Company and to that end
desire that the terms set forth in this Agreement shall supercede the term
governing termination of employment which are set forth in the Employment
Agreement;

         NOW, THEREFORE, it is agreed by and between the Company and Executive
as follows:

         1.       Resignation. Executive hereby agrees to resign as Vice
President of Developed Products and as Secretary of the Company, and to also
resign from any and all other positions held by Executive with the Company,
including, but not limited to, as a director of the Company or any subsidiary of
the Company, all effective as of January 1, 2001 (the "Separation Date").

         2.       Compensation. The Company will, in consideration for
Executive's resignation and his agreement to abide by the restrictions and
non-compete provisions contained in this Agreement, but subject to the
limitation set forth in Subsection 2(f), cause the Company, following
Executive's resignation, to pay or provide to or on behalf of Executive the
following:

                  (a)      One Hundred Five Thousand Dollars ($105,000.00) (the
         "Separation Payment"), less any applicable federal, state and local
         payroll and taxes and payable in 24 equal installments of Four Thousand
         Three Hundred and Seventy-Five ($4,375.00) on the same schedule as the
         Company's regular bi-weekly payroll payments in each month during
         calendar year 2001, beginning with the first payroll payment in January
         2001 and ending on the last payroll payment in December 2001.

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                  (b)      A car allowance payable monthly in the amount of
         Seven Hundred Fifty Dollars ($750.00) per month less any federal, state
         or local applicable taxes (the "Car Allowance") for the twelve (12)
         month period from January 1, 2001 to December 31, 2001.

                  (c)      In addition to the Separation Payment and the Car
         Allowance, the Company shall continue to make payments on Executive's
         behalf in accordance with its existing policy for medical coverage for
         Executive and his eligible dependents (the "Health Benefits") until the
         earlier of twelve months (12) months after the Separation Date, the
         date when Executive shall become covered by another medical plan, or
         the date, if ever, at which Executive shall determined to be in breach
         of the provisions of Section 3(a) or 4 of this Agreement.

                  (d)      The Bonus provided for by Paragraph 4(b) of the
         Employment Agreement shall be calculated and paid, in full, as provided
         in the Employment Agreement.

                  (e)      All stock options heretofore granted to Executive
         pursuant to the Company's 1997 Non-Qualified Stock Option Plan which
         have vested as of the date hereof or are scheduled to vest on or before
         March 17, 2001 (the "Options"), shall vest upon Executive's resignation
         and be exercisable for a period of one hundred twenty (120) days from
         the Separation Date (the "Exercise period"). If Executive so elects,
         the Options may be exercised on a cashless basis during the Exercise
         Period.

                  (f)      Notwithstanding the foregoing, in the event that
         Executive shall accept full-time employment with another employer, the
         Separation Payment, Car Allowance and Health Benefits provided for
         herein shall immediately terminate and the Company will have no further
         obligation to Executive with respect to same. In order the permit the
         Company to be informed as to Executive's employment status, Executive
         shall immediately advise the Company when he has accepted full-time
         employment with another employer. Failure of Executive to promptly
         report the acceptance of a new position shall entitle the Company to
         terminate the remaining Separation Payment, Car Allowance payments and
         Health Benefits and to seek restitution for any payments made to
         Executive hereunder. For purposes of this Agreement, "full-time
         employment" shall mean work for more than twenty (20) hours per week,
         but shall not include charitable or other work for which Executive
         receives no compensation.

         Other than the foregoing, and reimbursement for documented business
related expenses incurred prior to the date hereof, Executive shall not be
entitled to any other compensation or reimbursement from the Company from and
after the Separation Date and shall not be covered by or entitled to any
benefits under any of the Company's benefits or programs, including, but not
limited to, coverage under the Company's directors and officers insurance
policy.

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         3.       Post Employment Covenants.

                  (a)      Executive hereby covenants and agrees with the
Company that for a period (the "Restricted Period") of twenty-four (24) months
after the Separation Date, Executive shall not, without the prior written
consent of the Company, which consent shall be within the sole and exclusive
discretion of the Company, either directly or indirectly, on his own account or
as an executive, consultant, agent, partner, joint venturer, owner, officer,
director or shareholder of any other person, firm, corporation, partnership,
limited liability company or other entity, or in any other capacity, in any way:

                           (i)      Carry on, be engaged in or have any
                  financial interest in any business which is in competition
                  with the business of the Company. For purposes of this
                  Section 3, a business shall be deemed to be in competition
                  with the Company if it involves research and development work
                  involving any products, including, but not limited to, generic
                  during products, which would compete with Company products
                  which were, at the time of separation, being marketed by the
                  Company or which at such time were under study by the Company
                  and expected to be marketed within twelve (12) months of the
                  date of separation. Nothing in this Section 3 shall be
                  construed so as to preclude Executive from investing in any
                  publicly held company (though not one controlled by any member
                  of Executive's or Executive's spouse's family), provided
                  Executive's beneficial ownership of any class of such
                  company's securities does not exceed 5% of the outstanding
                  securities of such class;

                           (ii)     solicit any current supplier, customer or
                  client of the Company or any affiliate of the company or
                  anyone who was a supplier, customer or client at any time
                  during the twenty-four (24) month period immediately preceding
                  or following separation, excluding customers such as
                  wholesalers, managed care agencies, shippers, commercial and
                  investment banks, IR/PR agencies, scientific and computer
                  consultants, lawyers and manufacturers; as long as
                  manufacturers have extra capacity; provided, however, that
                  where minimum alternative allocation sources would not be
                  available, requests for exceptions to this restriction will be
                  determined by the Company on a case by case basis; or

                           (iii)    solicit, employ or engage any person who was
                  an employee of the Company or any affiliate of the Company at
                  any time during the twelve (12) month period immediately
                  preceding or following termination.

                  (b)      Following the Separation Date Executive shall:

                           (i)      For a period of twelve (12) months provide
                  the Company with all reasonable assistance necessary to permit
                  the Company to continue its business operations without
                  interruption and in a manner consistent with reasonable
                  business practices; provided, however, that such assistance
                  shall not require more than ten (10) hours per month of
                  assistance during the first three (3) months

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                  following the Separation Date nor more than four (4) hours per
                  month during the next nine (9) months following the Separation
                  Date, it being acknowledged and agreed that to the extent that
                  the Company shall require Executive to provide more consulting
                  time than is herein provided, then the Company shall pay
                  Executive a reasonable consulting fee per hour as agreed to by
                  the Company and Executive.

                           (ii)     Deliver to the Company possession of any and
                  all property owned or leased by the Company which may then be
                  in Executive's possession or under his control, including
                  without limitation any and all such keys, credit cards,
                  automobiles, equipment, supplies, books, records, files,
                  computer equipment, computer software and other such tangible
                  and intangible property of any description whatsoever.

                           (iii)    If, following the Termination Date,
                  Executive shall receive any mail addressed to the Company, or
                  the Company shall receive any personal mail addressed to
                  Executive, the receiving party shall immediately deliver such
                  mail, in its original envelope or package, to the Company or
                  Executive, as the case may be.

         4.       Confidentiality.

                  (a)      Executive agrees that "Confidential Information" (as
herein defined) obtained or developed by him during the course of his employment
with the Company is confidential and, accordingly, agrees that for a period of
five (5) years from the date hereof, he will not disclose to any person or use
for his own account, or for the account of others, directly or indirectly, any
of the Confidential Information without the prior written consent of the
Company, unless and then only to the extent that, such matters may be otherwise
generally available for use by the public and not as a result of his acts or
omissions to act. In particular, Executive shall not use or permit the use of
any Confidential Information for the purpose of trading in the common stock of
the Company.

                  As used herein, "Confidential Information" means any and all
information in the possession of or disclosed to the Executive (i) that pertains
or belongs to the Company or its customers and is not generally available to the
public, including, but not limited to, personnel information, customer lists,
supplier lists, product specifications and names, trade secrets, computer and
any other processed or collated data, computer programs, pricing, marketing and
advertising data; or (ii) that is related to business development plans or
distribution and marketing plans of the Company.

                  (b)      Executive agrees to keep the terms of this Agreement
confidential except that the source and amount of his income may be revealed as
necessary for tax, loan purposes and the like.

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                  5.       Remedies. Executive agrees that money damages cannot
         adequately compensate the Company in case of a breach or threatened
         breach of the covenants contained in Sections 3(a) or 4 and that,
         accordingly, the Company would be entitled to injunctive relief upon
         such breach. Executive understands that it is the Company's intent to
         have the covenants contained in Section 3(a) and 4 enforced to their
         fullest extent. Accordingly, Executive and the Company agree that, if
         any portion of the restrictions contained in Sections 3(a) or 4 are
         deemed unenforceable, the court shall construe and enforce these
         covenants to the fullest extent permitted by law.

                  6.       Enforcement Costs. If any legal action or other
         proceeding is brought for the enforcement of this Agreement, or because
         of an alleged dispute, breach, default or misrepresentation in
         connection with any provisions of this Agreement, the successful or
         prevailing party or parties shall be entitled to recover reasonable
         attorney's fees, court costs and all expenses even if not taxable as
         court costs (including, without limitation, all such fees, costs and
         expenses incident to appeal and other post-judgment proceedings),
         incurred in that action or proceeding, in addition to any other relief
         to which such party or parties may be entitled. Attorney's fees shall
         include, without limitation, paralegal fees, investigative fees,
         administrative costs, sales and use taxes and all other charges billed
         by the attorney to the prevailing party.

                  7.       Notices. Any and all notices necessary or desirable
         to be served hereunder shall be in writing and shall be

                           (a)      personally delivered, or

                           (b)      sent by certified mail, postage prepaid,
                  return receipt requested, or guaranteed overnight delivery by
                  a nationally recognized express delivery company, in each case
                  addressed to the intended recipient at the address set forth
                  below.

                           (c)      For notices sent to the Company:

                                    Horizon Pharmaceuticals, Inc.
                                    660 Hembree Parkway, Suite 106
                                    Roswell, Georgia 30076

                                    Telephone No.:  (770) 442-9707
                                    Facsimile No.:  (770) 442-9594

                           (d)      For notices sent to Executive:

                                    Gregory P. Hauck
                                    6665 Brookline Ct.
                                    Cumming, Georgia 30040

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         Either party hereto may amend the addresses for notices to such party
hereunder by delivery of a written notice thereof served upon the other party
hereto as provided herein. Any notice sent by certified mail as provided above
shall be deemed delivered on the third (3rd) business day next following the
postmark date which it bears.

         8.       Non-Assignability; Assignment in the Event of Acquisition or
Merger. This Agreement, and the benefits hereunder are not assignable or
transferable by Executive and the rights and obligations of the Company under
this Amendment will automatically be deemed to be assigned by the Company to any
corporation or entity acquiring all or substantially all of the assets of the
Company or to any corporation or entity with or into which the Company may be
merged or consolidated; provided, however, that in the event of Executive's
death, the Company shall make such payments as may then be due and owing to the
Executive, if any, to the Executive's estate.

         9.       Miscellaneous.

                  (a)      Entire Agreement; Amendment. This Agreement, and all
         documents delivered herewith, constitute the entire Agreement and
         understanding among the parties with respect to the matters contained
         herein, shall supersede all prior oral or written agreements or
         covenants of the parties, including, but not limited to, the Employment
         Agreement (it being acknowledged and agreed that in the event of any
         conflict between the provisions of this Agreement and the Employment
         Agreement, the provisions of this Agreement shall govern) and this
         Agreement shall be binding upon and insure to the benefit of the
         parties and their respective heirs, predecessors, personal
         representatives, successors and assigns, present or future. This
         Agreement shall not be modified or changed except by instrument in
         writing signed by or on behalf of each of the parties hereto.

                  (b)      Counterparts. This Agreement and all documents
         delivered pursuant hereto may be executed in one or more counterparts
         and each of every fully executed counterpart may be deemed to be an
         original hereof.

                  (c)      Headings. This descriptive headings in this Agreement
         are inserted for convenience only and shall not control or affect the
         meaning or construction of any of the provisions hereof.

                  (d)      Waiver. The failure of any party hereto to enforce at
         any time any of the provisions of this Agreement shall in no way be
         construed to be a waiver of any such provision, nor in any way to
         affect the validity of this Agreement or any provision, it being agreed
         that each provision hereof is, material, significant and essential to
         each of the party's agreements and undertakings hereunder. No waiver of
         any breach of this Agreement shall be held to be a waiver of any other
         or subsequent breach.

                  (e)      Invalidity. If any provision of this Agreement, or
         the application thereof to any person or circumstance, shall be
         construed for any reason and to any extent to be

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         invalid or unenforceable, but the extent of the invalidity or
         unenforceability does not destroy the basis of the bargain between the
         parties contained herein, the remainder of this Agreement, and the
         application of such provision to other persons or circumstances, shall
         not be affected thereby, but shall be enforced to the greatest extent
         permitted by law.

                  (f)      Expenses. Each of the parties hereto shall pay its
         own expenses, including, but not limited to, the fees of its separate
         counsel, in connection with this Agreement.

                  (g)      Choice of Law. This Agreement shall be construed in
         accordance with the laws of the State of Georgia, and the rights and
         obligations of the parties hereunder shall be construed and enforced in
         accordance with, and governed by the laws of the State of Georgia,
         without regard to principals of conflict of laws. Regardless of the
         residence of the parties, venue and forum shall be in the federal or
         state courts located in Fulton County, Georgia.

                  The Company and Executive, having read and understood this
         Amendment, and having consulted with advisors as appropriate, hereby
         each agree to be bound by its terms.

         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
day and date first above written.

                                  FIRST HORIZON PHARMACEUTICALS CORPORATION

                                  By: /s/ Balaji Venkataraman
                                     ---------------------------------
                                  Its:        VP/CFO
                                      --------------------------------

                                              /s/ Gregory P. Hauck
                                      --------------------------------
                                              Gregory P. Hauck

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