<PAGE>
                                                                    EXHIBIT 10.8


                           KING PHARMACEUTICALS, INC.

                                 INCENTIVE PLAN

                  LONG-TERM PERFORMANCE UNIT AWARD CERTIFICATE
                          (ONE-YEAR PERFORMANCE CYCLE)

     This Certificate, when executed by a duly authorized officer of King
Pharmaceuticals, Inc. (the "Company") and by Participant, evidences the grant by
the Company to the Participant named below of a Long-Term Performance Unit
Award.

<TABLE>
<S>                                     <C>
1. Name and Address of Participant:
                                        ----------------------------------------

                                        ----------------------------------------

                                        ----------------------------------------

2. Date of Grant:
                                        ----------------------------------------

3. Type of Grant:                       Long-Term Performance Unit Award


4. Target Number of
   Long-Term Performance Units:
                                        ----------------------------------------

5. Performance Cycle:                   The Performance Cycle shall being on January
                                        1, 2006 and end on December 31, 2006.

6. Vesting Period:                      The Vesting Period shall begin on January 1,
                                        2007 and end on December 31, 2008, except as
                                        otherwise set forth in the Long-Term
                                        Performance Unit Award Agreement.

7. Date of Payment:                     March 15, 2009, except as otherwise set forth in
                                        the Long-Term Performance Unit Award Agreement.

8. Performance Goals:
</TABLE>

     The number of Long-Term Performance Units earned by the Participant shall
be determined in accordance with the following grid. If the actual performance
results fall between two of the categories listed below, straight-line
interpolation will be used to determine the amount earned. The Financial
Objectives shall be listed and shall be calculated in the manner set forth in
Exhibit 1 hereto.
--------------------------------------------------------------------------------

<Table>
<S>                                                               <C>
 KING PHARMACEUTICALS, INC. ANNUAL PERFORMANCE V. STATED           PAYOUT--PERCENT OF TARGET
                FINANCIAL OBJECTIVES                              LONG-TERM PERFORMANCE UNITS
            DURING THE PERFORMANCE CYCLE                                   GRANTED

                   Above Stretch                                             200%
----------------------------------------------------------------------------------------------
                     Stretch                                                 200%
----------------------------------------------------------------------------------------------
                      Target                                                 100%
----------------------------------------------------------------------------------------------
                    Threshold                                                 50%
----------------------------------------------------------------------------------------------
                 Below Threshold                                        0% (no payout)
----------------------------------------------------------------------------------------------
</Table>




<PAGE>


     This Long-Term Performance Unit Award is subject to and governed by the
terms of this Long-Term Performance Unit Award Certificate, the Long-Term
Performance Unit Award Agreement attached hereto and incorporated by reference
herein and the Company's Incentive Plan.


                                       KING PHARMACEUTICALS, INC.


                                       By:
                                           ----------------------------------
                                           Name:
                                                 ----------------------------
                                           Title:
                                                 ----------------------------


                                       PARTICIPANT


                                       --------------------------------------


This Long-Term Performance Unit Award Certificate may be executed in more than
one counterpart, each of which shall be deemed an original, but all of which
together shall constitute but one and the same instrument. Facsimile or
photographic copies of originally signed copies of this Long-Term Performance
Unit Award Certificate will be deemed to be originals.


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<PAGE>


                                                                    Exhibit 10.8


                   LONG-TERM PERFORMANCE UNIT AWARD AGREEMENT.
                          (ONE YEAR PERFORMANCE CYCLE)
                   PURSUANT TO THE KING PHARMACEUTICALS, INC.
                                 INCENTIVE PLAN


     This Long-Term Performance Unit Award Agreement (the "Agreement") is made
as of the date set forth on the Long-Term Performance Unit Award Certificate
attached hereto (the "Grant Date") by King Pharmaceuticals, Inc. (the "Company")
and the individual identified on the Long-Term Performance Unit Award
Certificate (the "Participant") to grant a Long-Term Performance Unit Award by
the Company to the Participant on the terms and conditions set forth below:

     1. LONG-TERM PERFORMANCE UNIT AWARD.

     As of the Grant Date, subject to the terms, conditions and restrictions set
forth herein, the Company grants and issues to the Participant a Long-Term
Performance Unit Award for such number of Long-Term Performance Units as
indicated on the Long-Term Performance Unit Award Certificate (the "Long-Term
Performance Units") which may be earned during the Performance Cycle as
indicated on the Long-Term Performance Unit Award Certificate if the Performance
Goals set forth on the Long-Term Performance Unit Award Certificate are met.

     2. GOVERNING PLAN.

     The Long-Term Performance Unit Award shall be granted pursuant to and
(except as specifically set forth herein) subject in all respects to the
applicable provisions of the King Pharmaceuticals, Inc. Incentive Plan ("Plan"),
which are incorporated herein by reference. Terms not otherwise defined in this
Agreement have the meanings ascribed to them in the Plan.

     3. CALCULATION OF EARNED LONG-TERM PERFORMANCE UNITS.

     The Committee, in its sole discretion, will determine the number of
Long-Term Performance Units earned by the Participant at the end of the
Performance Cycle based on the attainment of the Performance Goals as set forth
on the Long-Term Performance Unit Award Certificate. The number of shares of
Common Stock ultimately earned and paid, if any, for such Long-Term Performance
Units will be determined based on the number of Long-Term Performance Units
actually earned and vested as set forth in Section 4 below, with one share of
Common Stock granted to the Participant for every earned and vested Long-Term
Performance Unit.

     4. VESTING OF LONG-TERM PERFORMANCE UNITS.

     Long-Term Performance Units earned will vest as set forth below:

          (a) Provided the Participant has continued employment through the end
of the Vesting Period set forth in the Long-Term Performance Unit Award
Certificate, one hundred percent (100%) of the earned Long-Term Performance
Units shall vest on the last day of such Vesting Period; or


                                  Exhibit 1-1

<PAGE>

          (b) In the event of the Participant's Separation from Service by
reason of death, Disability, Approved Retirement, Cause, resignation or any
other reason during the Performance Cycle, the vesting, forfeiture and payment
of Long-Term Performance Units shall be determined according to Section 9.2 and
Section 13.5 of the Plan, which requires that all payments comply with Section
409A of the Code.

     5. FORM AND TIMING OF PAYMENT.

     All payments of vested Long-Term Performance Units pursuant to this
Agreement will be made in the form of shares of Common Stock. Except as
otherwise provided in this Agreement, payment will be made by the Date of
Payment set forth in the Long-Term Performance Unit Award Certificate; provided,
however, if, the Participant is a "specified employee" (as defined under Section
409A of the Code) then such payment, if required by Section 409A of the Code,
will be made six months after the date of such Separation from Service.

     6. VOTING AND DIVIDEND RIGHTS.

     Except as specifically set forth in this Agreement, the Participant shall
not have voting or any other rights as a shareholder of the Company with respect
to Long-Term Performance Units. The Participant will obtain full voting and
other rights as a shareholder of the Company upon the payment of the Long-Term
Performance Units in shares of Common Stock as provided in Section 5 above.

     7. ADDITIONAL AGREEMENTS.

          (a) Tax Matters. The Long-Term Performance Units granted are subject
to appropriate income tax withholding and other deductions required by
applicable laws or regulations, and Participant and his successors will be
responsible for all income and other taxes payable as a result of a payout under
the Long-Term Performance Units or otherwise in connection with this Agreement.
The Company will have the power and the right to deduct or withhold, or require
the Participant or the Participant's beneficiary to remit to the Company, the
minimum necessary amount to satisfy federal, state, and local taxes, domestic or
foreign, required by law or regulation to be withheld with respect to any
taxable event arising as a result of this Agreement. The Company is not required
to provide any gross-up or other tax assistance. With respect to withholding
required upon any taxable event arising as a result of the Long-Term Performance
Units granted hereunder, the Company, unless notified otherwise by the
Participant in writing within thirty (30) days prior to the taxable event, will
satisfy the tax withholding requirement by withholding shares of Common Stock
having a Fair Market Value, equal to the total minimum statutory tax required to
be withheld on the transaction. The Participant agrees to pay to the Company
and/or its Subsidiaries any amount of tax that the Company, its and/or its
Subsidiaries may be required to withhold as a result of the Participant's
participation in the Plan that cannot be satisfied by the means previously
described.

          (b) Independent Advice; No Representations. Participant acknowledges
that (i) (s)he was free to use professional advisors of her/his choice in
connection with this Agreement, has received advice from her/his professional
advisors in connection with this Agreement, understands its meaning and import,
and is entering into this Agreement freely and without coercion or duress; and
(ii) (s)he has not received and is not relying upon any advice,


                                       2
<PAGE>

representations or assurances made by or on behalf of the Company or any Company
affiliate or any employee of or counsel to the Company regarding any tax or
other effects or implications of the Long-Term Performance Units or other
matters contemplated by this Agreement.

          (c) Value of Long-Term Performance Units. No representations or
promises are made to Participant regarding the value of the Long-Term
Performance Units or Company's business prospects. Participant acknowledges that
information about investment in Company stock, including financial information
and related risks, is contained in Company's SEC reports which have been made
available for Participant's review at any time before Participant's acceptance
of this Agreement. Further, Participant understands that the Company does not
provide tax or investment advice and acknowledges Company's recommendation that
Participant consult with independent specialists regarding such matters. Sale or
other transfer of the Company stock may be limited by and subject to Company
policies as well as applicable securities laws and regulations.

          (d) Adjustment in Capitalization. In the event of an Adjustment Event
that is a merger, consolidation, reorganization, liquidation, dissolution or
other similar transaction, then the Award pursuant to Section 1 of this
Agreement shall be deemed to pertain to the securities and other property,
including cash, to which a holder of the number of Long-Term Performance Units
would have been entitled to receive in connection with such Adjustment Event.

          (e) Change of Control. Upon a Change of Control, vesting, forfeiture
and payment shall occur with respect to the Long Term Performance Units in
accordance with Article 11 of the Plan.

          (f) No Right to Continued Employment. This Agreement does not confer
upon Participant any right to continue as an employee of the Company or its
subsidiary or to any particular employment tenure, nor does it limit in any way
the right of Company or its subsidiary to terminate Participant's services to
the Company or its subsidiary at any time, with or without cause.

          (g) Nontransferability. Long-Term Performance Units awarded pursuant
to this Agreement may not be sold, transferred, pledged, assigned or otherwise
alienated or hypothecated (a "Transfer") other than by will or by the laws of
descent and distribution, except as provided in the Plan. If any Transfer,
whether voluntary or involuntary, of Long-Term Performance Units is made, or if
any attachment, execution, garnishment, or lien will be issued against or placed
upon the Long-Term Performance Units, the Participant's right to such Long-Term
Performance Units will be immediately forfeited to the Company, and this
Agreement will lapse.

     8. GENERAL.

          (a) Successors and Assigns. This Agreement is personal in its nature
and Participant may not assign or transfer his/her rights under this Agreement.

          (b) Notices. Any notices, demands or other communications required or
desired to be given by any party shall be in writing and shall be validly given
to another party if served either personally or if deposited in the United
States mail, certified or registered, postage prepaid, return receipt requested.
If such notice, demand or other communication shall be served personally,
service shall be conclusively deemed made at the time of such personal service.
If


                                       3
<PAGE>

such notice, demand or other communication is given by mail, such notice shall
be conclusively deemed given forty-eight (48) hours after the deposit thereof in
the United States mail addressed to the party to whom such notice, demand or
other communication is to be given as hereinafter set forth:



     To the Company:                     King Pharmaceuticals, Inc.
                                         501 Fifth Street
                                         Bristol, TN 37620
                                         Attention:  _________________________

     To Participant: At his/her address of record as maintained in the Company's
files.

Any party may change its address for the purpose of receiving notices, demands
and other communications by providing written notice to the other party in the
manner described in this paragraph.

          (c) Entire Agreement. Except as this Agreement may expressly provide
otherwise, this Agreement, the Long-Term Performance Unit Award Certificate and
the Plan constitute the entire agreement and understanding of the Company and
Participant with respect to the subject matter hereof and thereof, and supersede
all prior written or verbal agreements and understandings between Participant
and the Company relating to such subject matter. This Agreement may only be
amended by written instrument signed by Participant and an authorized officer of
the Company.

          (d) Governing Law; Severability. This Agreement will be construed and
interpreted under the laws of the State of Tennessee applicable to agreements
executed and to be wholly performed within the State of Tennessee. If any
provision of this Agreement as applied to any party or to any circumstance is
adjudged by a court of competent jurisdiction to be void or unenforceable for
any reason, the invalidity of that provision shall in no way affect (to the
maximum extent permissible by law) the application of such provision under
circumstances different from those adjudicated by the court, the application of
any other provision of this Agreement, or the enforceability or invalidity of
this Agreement as a whole. If any provision of this Agreement becomes or is
deemed invalid, illegal or unenforceable in any jurisdiction by reason of the
scope, extent or duration of its coverage, then such provision shall be deemed
amended to the extent necessary to conform to applicable law so as to be valid
and enforceable or, if such provision cannot be so amended without materially
altering the intention of the parties, then such provision will be stricken and
the remainder of this Agreement shall continue in full force and effect.

          (e) Remedies. All rights and remedies provided pursuant to this
Agreement or by law shall be cumulative, and no such right or remedy shall be
exclusive of any other. A party may pursue any one or more rights or remedies
hereunder or may seek damages or specific performance in the event of another
party's breach hereunder or may pursue any other remedy by law or equity,
whether or not stated in this Agreement.

          (f) Interpretation. Headings herein are for convenience of reference
only, do not constitute a part of this Agreement, and will not affect the
meaning or interpretation of this


                                       4
<PAGE>

Agreement. References herein to Sections are references to the referenced
Section hereof, unless otherwise specified.

          (g) Waivers; Amendments. The waiver by either party of a breach of any
provision of this Agreement shall not operate or be construed as a waiver of any
later breach of that provision. This Agreement may be modified only by written
agreement signed by Participant and the Company.




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