Exhibit 4.18

                               GUARANTEE AGREEMENT

                                 By and Between

                                 OMNICARE, INC.,
                                  as Guarantor

                                       and

                              [                 ],
                                   as Trustee

                          Dated as of ________ __, 200_






                             Cross Reference Table*

                 Section of                            Section of
    Trust Indenture Act of 1939, as amended        Guarantee Agreement
    ---------------------------------------        -------------------

310(a)..........................................      4.1
310(b)..........................................      2.8; 4.1
310(c)..........................................      Inapplicable
311(a)..........................................      2.2(b)
311(b)..........................................      2.2(b)
311(c)..........................................      Inapplicable
312(a)..........................................      2.2(a); 2.9
312(b)..........................................      2.2(b); 2.9
312(c)..........................................      2.9
313(a)..........................................      2.3
313(b)..........................................      2.3
313(c)..........................................      2.3
313(d)..........................................      2.3
314(a)..........................................      2.4
314(b)..........................................      Inapplicable
314(c)..........................................      2.5
314(d)..........................................      Inapplicable
314(e)..........................................      2.5; 9.5
314(f)..........................................      Inapplicable
315(a)..........................................      3.1(d)
315(b)..........................................      2.7
315(c)..........................................      3.1(c)
315(d)..........................................      3.1(e)
316(a)..........................................      2.6; 5.4(a)
316(b)..........................................      5.3
316(c)..........................................      Inapplicable
317(a)..........................................      2.10
317(b)..........................................      Inapplicable
318(a)..........................................      2.1(b)
318(b)..........................................      2.1
318(c)..........................................      2.1(a)

- ----------
*    This cross-reference table does not constitute part of the agreement and
     shall not have any bearing upon the interpretation of any of its terms or
     provisions.


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                                Table of Contents

ARTICLE I INTERPRETATION AND DEFINITIONS.......................................1

   Section 1.1   Definitions...................................................1
   Section 1.2   Incorporation by Reference of Trust Indenture Act.............4
   Section 1.3   Rules of Construction.........................................5

ARTICLE II TRUST INDENTURE ACT.................................................5

   Section 2.1   Trust Indenture Act; Application..............................5
   Section 2.2   Lists of Holders..............................................5
   Section 2.3   Reports by Guarantee Trustee..................................6
   Section 2.4   Periodic Reports to Guarantee Trustee.........................6
   Section 2.5   Evidence of Compliance with Conditions Precedent..............6
   Section 2.6   Guarantee Event of Default; Waiver............................6
   Section 2.7   Guarantee Event of Default; Notice............................6
   Section 2.8   Conflicting Interests.........................................7

ARTICLE III POWERS, DUTIES AND RIGHTS OF GUARANTEE TRUSTEE.....................7

   Section 3.1   Duties of Guarantee Trustee...................................7
   Section 3.2   Rights of Guarantee Trustee...................................8

ARTICLE IV GUARANTEE TRUSTEE..................................................10

   Section 4.1   Eligibility; Disqualification................................10
   Section 4.2   Replacement of Guarantee Trustee.............................10

ARTICLE V GUARANTEE ..........................................................11

   Section 5.1   Guarantee....................................................11
   Section 5.2   Waiver of Notice and Demand..................................11
   Section 5.3   Obligations Not Affected.....................................11
   Section 5.4   Rights of Holders............................................12
   Section 5.5   Guarantee of Payment.........................................13
   Section 5.6   Subrogation..................................................13
   Section 5.7   Independent Obligations......................................13

ARTICLE VI LIMITATIONS ON TRANSACTIONS; SUBORDINATION.........................14

   Section 6.1   Limitations on Transactions..................................14
   Section 6.2   Subordination................................................14

ARTICLE VII TERMINATION ......................................................15

   Section 7.1   Termination..................................................15

ARTICLE VIII INDEMNIFICATION..................................................15

   Section 8.1   Exculpation..................................................15
   Section 8.2   Compensation and Indemnity...................................16

ARTICLE IX MISCELLANEOUS......................................................16

   Section 9.1   Successors and Assigns.......................................16
   Section 9.2   Amendments...................................................16


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   Section 9.3   Notices......................................................17
   Section 9.4   Counterparts.................................................17
   Section 9.5   Benefit......................................................17
   Section 9.6   Governing Laws...............................................17


                                       iii






                               GUARANTEE AGREEMENT

     WHEREAS, pursuant to the Trust Agreement (as defined herein), the Omnicare
Capital Trust [I / II / III] (the "Trust") is issuing on the date hereof
$________ aggregate liquidation amount of preferred securities, having a
liquidation amount of $____ per security and designated the "____% Trust
Preferred Securities" of the Trust (the "Trust Preferred Securities") and
$________ aggregate liquidation amount of common securities, having a
liquidation amount of $____ per security and designated the "____% Trust Common
Securities" of the Trust (together with the Trust Preferred Securities, the
"Trust Securities");

     WHEREAS, as incentive for the Holders (as defined herein) to purchase the
Trust Preferred Securities, Omnicare, Inc. (the "Guarantor"), desires
irrevocably and unconditionally to agree, to the extent set forth in this
Guarantee, to pay to the Holders of the Trust Preferred Securities the Guarantee
Payments (as defined herein) and to make certain other payments on the terms and
conditions set forth herein; and

     NOW, THEREFORE, in consideration of the purchase by each Holder of Trust
Preferred Securities, which purchase the Guarantor hereby agrees shall benefit
the Guarantor, the Guarantor executes and delivers this Guarantee for the
benefit of such Holders.

                                    ARTICLE I

                         INTERPRETATION AND DEFINITIONS

          Section 1.1 Definitions.

     "Affiliate" of any specified Person means any other Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person. For the purposes of this definition,
"control" when used with respect to any specified Person means the power to
direct the management and policies of such Person, directly or indirectly,
whether through the ownership of voting securities, by contract or otherwise;
and the terms "controlling" and "controlled" have meanings correlative to the
foregoing.

     "Business Day" has the meaning specified in the Trust Agreement.

     "Covered Person" means a Holder or beneficial owner of Trust Preferred
Securities.

     "Depositor" has the meaning specified in the Trust Agreement.

     "Distributions" has the meaning specified in the Trust Agreement.

     "Event of Default" has the meaning specified in the Indenture.






     "Extension Period" means such period or periods as the Guarantor shall
defer the payment of interest on the Subordinated Debt Securities pursuant to
the terms thereof and pursuant to the Indenture.

     "Global Security" has the meaning specified in the Trust Agreement.

     "Guarantee Event of Default" means a default by the Guarantor on any of its
payment or other obligations under this Guarantee.

     "Guarantee Payments" means the following payments or distributions, without
duplication, with respect to the Trust Preferred Securities, to the extent not
paid by or on behalf of the Trust: (i) any accrued and unpaid Distributions that
are required to be paid on such Trust Preferred Securities to the extent the
Trust has sufficient funds legally and immediately available therefor at the
time, (ii) the Redemption Price, including all accrued and unpaid Distributions
to the date of redemption, with respect to any Trust Preferred Securities called
for redemption by the Trust, to the extent the Trust shall have sufficient funds
legally and immediately available therefor at the time or (iii) upon a voluntary
or involuntary dissolution, winding-up or termination of the Trust (other than
in connection with the distribution of Subordinated Debt Securities to the
holders of Trust Securities as provided in the Trust Agreement or the redemption
of all the Trust Preferred Securities), the lesser of (a) the sum of the
liquidation amount and all accrued and unpaid Distributions on the Trust
Preferred Securities to the date of payment, to the extent the Trust has
sufficient funds legally and immediately available therefor and (b) the amount
of assets of the Trust remaining available for distribution to Holders of Trust
Preferred Securities in liquidation of the Trust (in either case, the
"Liquidation Distribution").

     "Guarantee Trustee" means [               ], a national banking association
organized under the laws of the United States, until a successor Guarantee
Trustee has been appointed and has accepted such appointment pursuant to the
terms of this Guarantee and thereafter means each such Successor Guarantee
Trustee.

     "Guarantor" has the meaning specified in the recitals hereto.

     "Holder" shall mean any holder, as registered on the books and records of
the Trust, of any Trust Preferred Securities; provided, however, that in
determining whether the holders of the requisite percentage of Trust Preferred
Securities have given any request, notice, consent or waiver hereunder, "Holder"
shall not include the Guarantor or any Affiliate of the Guarantor.

     "Indemnified Person" means the Guarantee Trustee, or any officers,
directors, employees, shareholders or agents of the Guarantee Trustee.

     "Indenture" means the Subordinated Debt Securities Indenture, dated as of
________ __, 200_, between the Guarantor and ________, as Trustee, pursuant to
which the Subordinated Debt Securities are issued and as thereafter amended or
supplemented from time to time.


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     "Liquidation Distribution" has the meaning specified in the definition of
"Guarantee Payments" above.

     "List of Holders" has the meaning assigned to it in Section 2.2 hereof.

     "Majority in Liquidation Amount" means Holders of outstanding Trust
Preferred Securities, voting separately as a class, who are the record owners of
more than 50% of the aggregate liquidation amount (including the stated amount
that would be paid on redemption, liquidation or otherwise, plus accrued and
unpaid Distributions to the date upon which the voting percentages are
determined) of all outstanding Trust Preferred Securities. In determining
whether the Holders of the requisite amount of Trust Preferred Securities have
voted, Trust Preferred Securities which are owned by the Guarantor or any
Affiliate of the Guarantor or any other obligor on the Trust Preferred
Securities shall be disregarded for the purpose of any such determination.

     "Officer" means the Chairman of the Board, any Vice Chairman, the Chief
Executive Officer, the President, any Vice President, the Treasurer, the
Secretary, any Assistant Treasurer or any Assistant Secretary of the Depositor.

     "Officers' Certificate" means a certificate signed by the Chairman of the
Board, the President or a Vice President, and by the Treasurer, an Assistant
Treasurer, the Secretary or an Assistant Secretary, of the Guarantor, and
delivered to the Trustee. Any Officers' Certificate delivered with respect to
compliance with a condition or covenant provided for in this Guarantee shall
include:

          (a) a statement that each officer signing the Officers' Certificate
     has read the covenant or condition and the definitions relating thereto;

          (b) a brief statement of the nature and scope of the examination or
     investigation undertaken by each officer in rendering the Officers'
     Certificate;

          (c) a statement that each such officer has made such examination or
     investigation as, in such officer's opinion, is necessary to enable such
     officer to express an informed opinion as to whether or not such covenant
     or condition has been complied with; and

          (d) a statement as to whether, in the opinion of each such officer,
     such condition or covenant has been complied with.

     "Person" means an individual, corporation, partnership, joint venture,
trust, limited liability company or corporation, unincorporated organization or
government or any agency or political subdivision thereof.

     "Property Trustee" has the meaning specified in the Trust Agreement.

     "Redemption Price" has the meaning specified in the Trust Agreement.

     "Registrar" has the meaning specified in the Trust Agreement.


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     "Responsible Officer" means, with respect to the Guarantee Trustee, any
officer with direct responsibility for the administration of this Guarantee and
also means, with respect to a particular corporate trust matter, any other
officer to whom any corporate trust matter is referred because of his or her
knowledge of and familiarity with a particular subject.

     "Senior Indebtedness" has the meaning specified in the Indenture.

     "Subordinated Debt Securities" means the series of subordinated debt
securities issued by the Guarantor designated the "____% Subordinated Debt
Securities due ____" held by the Property Trustee.

     "Successor Guarantee Trustee" means a successor Guarantee Trustee
possessing the qualifications to act as Guarantee Trustee under Section 4.1.

     "Trust" has the meaning specified in the Trust Agreement.

     "Trust Agreement" means the Amended and Restated Trust Agreement, dated as
of __________ __, 200_, as the same may be modified, amended or supplemented in
accordance with the applicable provisions thereof, including all exhibits
thereto, including, for all purposes of such Amended and Restated Trust
Agreement and any modification, amendment or supplement, the provisions of the
Trust Indenture Act that are deemed to be a part of and govern such Amended and
Restated Trust Agreement and any such modification, amendment or supplement
thereto, respectively.

     "Trust Preferred Securities" has the meaning specified in the recitals
hereto. In the event that pursuant to the Trust Agreement, the Trust and the
Depositor grant an Underwriters' Overallotment Option (as defined in the Trust
Agreement) to certain underwriters or initial purchasers, as the case may be,
such that an additional amount of Trust Preferred Securities may be issued
pursuant to the terms of the Trust Agreement, then the defined term "Trust
Preferred Securities" shall include such additional Trust Preferred Securities.

     "Trust Securities" has the meaning specified in the recitals hereto.

     "TIA" means, to the extent required by any such amendment, the Trust
Indenture Act of 1939 as so amended.

          Section 1.2 Incorporation by Reference of Trust Indenture Act.

     Whenever this Guarantee refers to a provision of the TIA, the provision is
incorporated by reference in and made a part of this Guarantee. All terms used
in this Guarantee that are defined by the TIA, defined by the TIA's reference to
another statute or defined by Securities and Exchange Commission rule under the
TIA and not otherwise defined herein are used herein as so defined.


                                       4






          Section 1.3 Rules of Construction.

     Unless the context otherwise requires:

          (a) a term has the meaning assigned to it;

          (b) "or" is not exclusive;

          (c) words in the singular include the plural, and in the plural
     include the singular; and

          (d) provisions apply to successive events and transactions.

                                   ARTICLE II

                               TRUST INDENTURE ACT

          Section 2.1 Trust Indenture Act; Application.

          (a) This Guarantee is subject to the provisions of the TIA that are
     required to be part of this Guarantee and shall, to the extent applicable,
     be governed by such provisions.

          (b) If and to the extent that any provision of this Guarantee limits,
     qualifies or conflicts with the duties imposed by Sections 310 to 317,
     inclusive, of the TIA, such imposed duties shall control.

          Section 2.2 Lists of Holders.

          (a) The Guarantor shall furnish to the Guarantee Trustee a list of the
     names and addresses of the Holders ("List of Holders") in such form and as
     of such date as the Guarantee Trustee may reasonably require. The Guarantor
     shall furnish such List of Holders (i) within 30 days after receiving a
     written request from the Guarantee Trustee, such list to be as of a date no
     more than 15 days before such list is provided to the Guarantee Trustee,
     and (ii) unless the Trust Preferred Securities are represented by one or
     more Global Securities, at least one Business Day prior to the date for
     payment of Distributions, such list to be as of the record date relating to
     the payment of such Distributions. However, the Guarantor shall not be
     obligated to provide such List of Holders at any time the List of Holders
     does not differ from the most recent List of Holders given to the Guarantee
     Trustee by the Guarantor or at any time the Guarantee Trustee is the
     Registrar under the Trust Agreement. The Guarantee Trustee shall preserve,
     in as current a form as is reasonably practicable, all information
     contained in any List of Holders given to it, provided that the Guarantee
     Trustee may destroy any List of Holders previously given to it on receipt
     of a new List of Holders.

          (b) The Guarantee Trustee shall comply with its obligations under
     Sections 311(a), 311(b) and 312(b) of the TIA.


                                       5






          Section 2.3 Reports by Guarantee Trustee.

     Within 60 days after ________ of each year (commencing with the year of the
first anniversary of the issuance of the Trust Preferred Securities), the
Guarantee Trustee shall provide to the Holders such reports as are required by
Section 313(a) of the TIA (if any) in the form and in the manner provided by
Section 313 of the TIA. The Guarantee Trustee shall also comply with the other
requirements of Section 313 of the TIA. The Guarantor shall promptly notify the
Guarantee Trustee when the Trust Preferred Securities are listed on any stock
exchange.

          Section 2.4 Periodic Reports to Guarantee Trustee.

     The Guarantor shall provide to the Guarantee Trustee such documents,
reports and information as required by Section 314(a) (if any) of the TIA and
the compliance certificate required by Section 314(a)(4) of the TIA in the form,
in the manner and at the times required by Section 314(a) of the TIA, provided
that such compliance certificate shall be delivered on or before 120 days after
the end of each fiscal year of the Guarantor.

          Section 2.5 Evidence of Compliance with Conditions Precedent.

     The Guarantor shall provide to the Guarantee Trustee such evidence of
compliance with any conditions precedent, if any, provided for in this Guarantee
that relate to any of the matters set forth in Section 314(c) of the TIA. Any
certificate or opinion required to be given by an officer pursuant to Section
314(c)(1) may be given in the form of an Officers' Certificate.

          Section 2.6 Guarantee Event of Default; Waiver.

     The Holders of a Majority in Liquidation Amount of the Trust Preferred
Securities may, by vote or written consent, on behalf of all of the Holders,
waive any past Guarantee Event of Default and its consequences. Upon such
waiver, any such Guarantee Event of Default shall cease to exist, and any
Guarantee Event of Default arising therefrom shall be deemed to have been cured,
for every purpose of this Guarantee, but no such waiver shall extend to any
subsequent or other default or Guarantee Event of Default or impair any right
consequent thereon.

          Section 2.7 Guarantee Event of Default; Notice.

          (a) If a Guarantee Event of Default occurs and is continuing and if it
     is known to a Responsible Officer of the Guarantee Trustee, the Guarantee
     Trustee shall mail to each Holder notice of a Guarantee Event of Default
     within 90 days after it occurs or, if later, after a Responsible Officer of
     the Guarantee Trustee has knowledge of such Guarantee Event of Default. The
     Guarantee Trustee may withhold the notice if and so long as its corporate
     trust committee or a committee of its Responsible Officers in good faith
     determines that withholding the notice is in the interests of the Holders.


                                       6






          (b) The Guarantee Trustee shall not be deemed to have knowledge of any
     Guarantee Event of Default unless the Guarantee Trustee shall have received
     written notice, or a Responsible Officer charged with the administration of
     the Trust Agreement shall have obtained written notice, of such Guarantee
     Event of Default.

          Section 2.8 Conflicting Interests.

     The Trust Agreement shall be deemed to be specifically described in this
Guarantee for the purposes of clause (i) of the first proviso contained in
Section 310(b) of the TIA.

                                   ARTICLE III

                 POWERS, DUTIES AND RIGHTS OF GUARANTEE TRUSTEE

          Section 3.1 Duties of Guarantee Trustee

          (a) This Guarantee shall be held by the Guarantee Trustee on behalf of
     the Trust for the benefit of the Holders, and the Guarantee Trustee shall
     not transfer this Guarantee to any Person except a Holder exercising his or
     her rights pursuant to Section 5.4(b) or to a Successor Guarantee Trustee
     on acceptance by such Successor Guarantee Trustee of its appointment to act
     as Successor Guarantee Trustee. The right, title and interest of the
     Guarantee Trustee in and to this Guarantee shall automatically vest in any
     Successor Guarantee Trustee, and such vesting and succession of title shall
     be effective upon acceptance of appointment whether or not conveyance
     documents have been executed and delivered pursuant to the appointment of
     such Successor Guarantee Trustee.

          (b) If a Guarantee Event of Default has occurred and is continuing,
     the Guarantee Trustee shall enforce this Guarantee for the benefit of the
     Holders.

          (c) The Guarantee Trustee, before the occurrence of any Guarantee
     Event of Default and after the curing or waiving of all Guarantee Events of
     Default that may have occurred, shall undertake to perform only such duties
     as are specifically set forth in this Guarantee, and no implied covenants
     shall be read into this Guarantee against the Trustee. If a Guarantee Event
     of Default has occurred and is continuing, the Guarantee Trustee shall
     exercise the rights and powers vested in it by this Guarantee and use the
     same degree of care and skill in its exercise thereof as a prudent man
     would exercise or use under the circumstances in the conduct of his own
     affairs.

          (d) No provision of this Guarantee shall be construed to relieve the
     Guarantee Trustee from liability for its own negligent action, its own
     negligent failure to act, or its own willful misconduct, except that:

          (i) prior to the occurrence of any Event of Default and after the
     curing or waiving of all such Guarantee Events of Default that may have
     occurred:


                                       7






               (A) the duties and obligations of the Guarantee Trustee shall be
          determined solely by the express provisions of this Guarantee, and the
          Guarantee Trustee shall not be liable except for the performance of
          such duties and obligations as are specifically set forth in this
          Guarantee; and

               (B) in the absence of bad faith on the part of the Guarantee
          Trustee, the Guarantee Trustee may conclusively rely, as to the truth
          of the statements and the correctness of the opinions expressed
          therein, upon any certificates or opinions furnished to the Guarantee
          Trustee and conforming to the requirements of this Guarantee; but in
          the case of any such certificates or opinions that by any provision
          hereof are specifically required to be furnished to the Guarantee
          Trustee, the Guarantee Trustee shall be under a duty to examine the
          same to determine whether or not they conform to the requirements of
          this Guarantee;

          (ii) the Guarantee Trustee shall not be liable for any error of
     judgment made in good faith by a Responsible Officer of the Guarantee
     Trustee, unless it shall be proved that the Guarantee Trustee was negligent
     in ascertaining the pertinent facts upon which such judgment was made;

          (iii) the Guarantee Trustee shall not be liable with respect to any
     action taken or omitted to be taken by it in good faith in accordance with
     the direction of the Holders of a Majority in Liquidation Amount of the
     Trust Preferred Securities relating to the time, method and place of
     conducting any proceeding for any remedy available to the Guarantee
     Trustee, or exercising any trust or power conferred upon the Guarantee
     Trustee under this Guarantee; and

          (e) no provision of this Guarantee shall require the Guarantee Trustee
     to expend or risk its own funds or otherwise incur personal financial
     liability in the performance of any of its duties or in the exercise of any
     of its rights or powers, if the Guarantee Trustee shall have reasonable
     grounds for believing that the repayment of such funds or liability is not
     reasonably assured to it under the terms of this Guarantee or adequate
     indemnity against such risk or liability is not reasonably assured to it.

          Section 3.2 Rights of Guarantee Trustee.

          (a) Subject to the provisions of Section 3.1:

          (i) the Guarantee Trustee may rely and shall be fully protected in
     acting or refraining from acting upon any resolution, certificate,
     statement, instrument, opinion, report, notice, request, direction,
     consent, order, bond, debenture, note, other evidence of indebtedness or
     other paper or document believed by it to be genuine and to have been
     signed, sent or presented by the proper party or parties;

          (ii) any direction or act of the Guarantor contemplated by this
     Guarantee shall be sufficiently evidenced by an Officers' Certificate;


                                       8






          (iii) whenever, in the administration of this Guarantee, the Guarantee
     Trustee shall deem it desirable that a matter be proved or established
     before taking, suffering or omitting any action hereunder, the Guarantee
     Trustee (unless other evidence is herein specifically prescribed) may, in
     the absence of bad faith on its part, request and rely upon an Officers'
     Certificate which, upon receipt of such request, shall be promptly
     delivered by the Guarantor;

          (iv) The Guarantee Trustee may consult with counsel of its choice, and
     the written advice or opinion of such counsel with respect to legal matters
     shall be full and complete authorization and protection in respect of any
     action taken, suffered or omitted by it hereunder in good faith and in
     accordance with such advice or opinion; such counsel may be counsel to the
     Guarantor or any of its Affiliates and may include any of its employees,
     the Guarantee Trustee shall have the right at any time to seek instructions
     concerning the administration of this Guarantee from any court of competent
     jurisdiction;

          (v) the Guarantee Trustee shall not be bound to make any investigation
     into the facts or matters stated in any resolution, certificate, statement,
     instrument, opinion, report, notice, request, direction, consent, order,
     bond, debenture, note, other evidence of indebtedness or other paper or
     document, but the Guarantee Trustee, in its discretion, may make such
     further inquiry or investigation into such facts or matters as it may see
     fit;

          (vi) the Guarantee Trustee may execute any of the trusts or powers
     hereunder or perform any duties hereunder either directly or by or through
     agents or attorneys, and the Guarantee Trustee shall not be responsible for
     any misconduct or negligence on the part of any agent or attorney appointed
     with due care by it hereunder; and

          (vii) The Guarantee Trustee shall be under no obligation to exercise
     any of the rights or powers vested in it by this Guarantee at the request
     or direction of any of the Holders unless such Holders shall have offered
     to the Guarantee Trustee reasonable security or indemnity against the
     costs, expenses and liabilities which might be incurred by it in compliance
     with such request or direction, including such reasonable advances as may
     be requested by the Guarantee Trustee; provided, that nothing contained in
     this Section 3.2(f) shall be taken to relieve the Guarantee Trustee, upon
     the occurrence of a Guarantee Event of Default, of its obligation to
     exercise the rights and powers vested in it by this Guarantee in the manner
     provided by Section 3.1(c).

          (viii) Whenever in the administration of this Guarantee, the Guarantee
     Trustee shall deem it desirable to receive instructions with respect to
     enforcing any remedy or right or taking any other action hereunder, the
     Guarantee Trustee (A) may request written instructions from the Holders of
     a Majority in Liquidation Amount of the Trust Preferred Securities, (B) may
     refrain from enforcing such remedy or right or taking such other action
     until such written


                                       9






     instructions are received and (C) shall be protected in conclusively
     relying on or acting in accordance with such written instructions.

               (b) No provision of this Guarantee shall be deemed to impose any
          duty or obligation on the Guarantee Trustee to perform any act or acts
          or exercise any right, power, duty or obligation conferred or imposed
          on it in any jurisdiction in which it shall be illegal, or in which
          the Guarantee Trustee shall be unqualified or incompetent to act in
          accordance with applicable law, to perform any such act or acts or to
          exercise any such right, power, duty or obligation. No permissive
          power or authority available to the Guarantee Trustee shall be
          construed to be a duty.

                                   ARTICLE IV

                                GUARANTEE TRUSTEE

          Section 4.1 Eligibility; Disqualification.

     This Guarantee shall always have a Guarantee Trustee who satisfies the
requirements of Sections 310(a)(1), (2) and (5) of the TIA. The Guarantee
Trustee shall always have a combined capital and surplus of at least $50,000,000
as set forth in its most recent published annual report of condition. The
Guarantee Trustee shall comply with Section 310(b) of the TIA.

          Section 4.2 Replacement of Guarantee Trustee.

          (a) Subject to Section 4.2(b), the Guarantee Trustee may be appointed
     or removed without cause at any time by the Guarantor.

          (b) The Guarantee Trustee shall not be removed until a Successor
     Guarantee Trustee has been appointed and has accepted such appointment by
     written instrument executed by such Successor Guarantee Trustee and
     delivered to the Guarantor.

          (c) The Guarantee Trustee appointed to office shall hold office until
     a Successor Guarantee Trustee shall have been appointed or until its
     removal or resignation. The Guarantee Trustee may resign from office
     (without need for prior or subsequent accounting) by an instrument in
     writing executed by the Guarantee Trustee and delivered to the Guarantor,
     which resignation shall not take effect until a Successor Guarantee Trustee
     has been appointed and has accepted such appointment by instrument in
     writing executed by such Successor Guarantee Trustee and delivered to the
     Guarantor and the resigning Guarantee Trustee.

          (d) If a Successor Guarantee Trustee does not take office within 60
     days after the retiring Guarantee Trustee resigns or is removed, the
     retiring Guarantee Trustee, may petition any court of competent
     jurisdiction for the appointment of a Successor Guarantee Trustee.


                                       10






          (e) If the Guarantee Trustee fails to comply with Section 4.1, any
     Holder may petition any court of competent jurisdiction for the removal of
     the Guarantee Trustee and the appointment of a Successor Guarantee Trustee.

          (f) A Successor Guarantee Trustee shall deliver a written acceptance
     of its appointment to the retiring Guarantee Trustee and to the Guarantor.
     Immediately after that, the retiring Guarantee Trustee shall transfer all
     property held by it as Guarantee Trustee to the Successor Guarantee
     Trustee, the resignation or removal of the retiring Guarantee Trustee shall
     become effective, and the Successor Guarantee Trustee shall have all the
     rights, powers and duties of the Guarantee Trustee under this Guarantee. A
     Successor Guarantee Trustee shall mail a notice of its succession to each
     Holder. Notwithstanding replacement of the Guarantee Trustee pursuant to
     this Section 4.2, the Guarantor's obligations under Section 8.2 hereof
     shall continue for the benefit of the retiring Guarantee Trustee with
     respect to expenses and liabilities incurred by it prior to such
     replacement.

                                    ARTICLE V

                                    GUARANTEE

          Section 5.1 Guarantee.

     The Guarantor irrevocably and unconditionally agrees to pay in full to the
Holders the Guarantee Payments (without duplication of amounts theretofore paid
by the Trust), as and when due, regardless of any defense, right of set-off or
counterclaim that the Guarantor may have or assert against any Person. The
Guarantor's obligation to make a Guarantee Payment may be satisfied by direct
payment of the required amounts by the Guarantor to the Holders or by causing
the Trust to pay such amounts to the Holders. Notwithstanding anything to the
contrary herein, the Guarantor retains all of its rights to extend the interest
payment period on the Subordinated Debt Securities to the extent permitted by
the Indenture and the Guarantor shall not be obligated hereunder to make any
Guarantee Payments during any Extension Period with respect to the Distributions
on the Securities.

          Section 5.2 Waiver of Notice and Demand.

     The Guarantor hereby waives notice of acceptance of this Guarantee and of
any liability to which it applies or may apply, presentment, demand for payment,
any right to require a proceeding first against the Trust or any other Person
before proceeding against the Guarantor, protest, notice of nonpayment, notice
of dishonor, notice of redemption and all other notices and demands.

          Section 5.3 Obligations Not Affected.

     The obligations of the Guarantor to make the Guarantee Payments under this
Guarantee shall in no way be affected or impaired by reason of the happening
from time to time of any of the following:


                                       11






          (a) The release or waiver, by operation of law or otherwise, of the
     performance or observance by the Trust of any express or implied agreement,
     covenant, term or condition relating to the Trust Preferred Securities to
     be performed or observed by the Trust;

          (b) The extension of time for the payment by the Trust of all or any
     portion of the Distributions, Redemption Price, Liquidation Distribution or
     any other sums payable under the terms of the Trust Preferred Securities or
     the extension of time for the performance of any other obligation under,
     arising out of, or in connection with the Trust Preferred Securities (other
     than an extension of time for payment of Distributions, Redemption Price,
     Liquidation Distribution or other sum payable that results from the
     extension of any interest payment period on the Subordinated Debt
     Securities permitted by the Indenture);

          (c) Any failure, omission, delay or lack of diligence on the part of
     the Property Trustee or the Holders to enforce, assert or exercise any
     right, privilege, power or remedy conferred on the Property Trustee or the
     Holders pursuant to the terms of the Trust Preferred Securities, or any
     action on the part of the Trust granting indulgence or extension of any
     kind;

          (d) The voluntary or involuntary liquidation, dissolution, sale of any
     collateral, receivership, insolvency, bankruptcy, assignment for the
     benefit of creditors, reorganization, arrangement, composition or
     readjustment of debt of, or other similar proceedings affecting, the Trust
     or any of the assets of the Trust;

          (e) Any invalidity of, or defect or deficiency in, the Trust Preferred
     Securities;

          (f) The settlement or compromise of any obligation guaranteed hereby
     or hereby incurred; or

          (g) Any other circumstance whatsoever that might otherwise constitute
     a legal or equitable discharge or defense of a guarantor, it being the
     intent of this Section 5.3 that the obligations of the Guarantor hereunder
     shall be absolute and unconditional under any and all circumstances.

There shall be no obligation of the Guarantee Trustee or the Holders to give
notice to or obtain consent of the Guarantor or any other Person with respect to
the happening of any of the foregoing. No setoff, counterclaim, reduction or
diminution of any obligation, or any defense of any kind or nature that the
Guarantor has or may have against any Holder shall be available hereunder to the
Guarantor against such Holder to reduce the payments to it under this Guarantee.

          Section 5.4 Rights of Holders.

          (a) The Guarantor expressly acknowledges that: (i) this Guarantee
     Agreement will be deposited with the Guarantee Trustee to be held for the
     benefit of the Holders; (ii) the Guarantee Trustee has the right to enforce
     this Guarantee


                                       12






     Agreement on behalf of the Holders; (iii) the Holders of a Majority in
     Liquidation Amount of the Preferred Securities have the right to direct the
     time, method and place of conducting any proceeding for any remedy
     available to the Guarantee Trustee in respect of this Guarantee Agreement
     or exercising any trust or power conferred upon the Guarantee Trustee under
     this Guarantee Agreement, provided that such direction shall not be in
     conflict with any rule of law or with this Guarantee Agreement, and could
     not involve the Guarantee Trustee in personal liability in circumstances
     where reasonable indemnity would not be adequate; and (iv) any Holder may
     institute a legal proceeding directly against the Guarantor to enforce its
     rights under this Guarantee Agreement, without first instituting a legal
     proceeding against or requesting or directing that action be taken by the
     Guarantee Trustee or any other Person; it being understood and intended
     that no one or more of such Holders shall have any right in any manner
     whatsoever by virtue of, or by availing of, any provision of this Guarantee
     Agreement to affect, disturb or prejudice the rights of any other of such
     Holders or to obtain or to seek to obtain priority or preference over any
     other of such Holders or to enforce any right under this Guarantee
     Agreement, except in the manner herein provided and for the equal and
     ratable benefit of all of such Holders.

          Section 5.5 Guarantee of Payment.

     This Guarantee creates a guarantee of payment and not of collection.

          Section 5.6 Subrogation.

     The Guarantor shall be subrogated to all (if any) rights of the Holders
against the Trust in respect of any amounts paid to such Holders by the
Guarantor under this Guarantee; provided, however, that the Guarantor shall not
(except to the extent required by mandatory provisions of law) be entitled to
enforce or exercise any right that it may acquire by way of subrogation or any
indemnity, reimbursement or other agreement, in all cases as a result of payment
under this Guarantee, if at the time of any such payment, any amounts are due
and unpaid under this Guarantee. If any amount shall be paid to the Guarantor in
violation of the preceding sentence, the Guarantor agrees to hold such amount in
trust for the Holders and to pay over such amount to the Guarantee Trustee for
the benefit of the Holders.

          Section 5.7 Independent Obligations.

     The Guarantor acknowledges that its obligations hereunder are independent
of the obligations of the Trust with respect to the Trust Preferred Securities,
and that the Guarantor shall be liable as principal and as debtor hereunder to
make Guarantee Payments pursuant to the terms of this Guarantee notwithstanding
the occurrence of any event referred to in subsections 5.3(a) through 5.3(g),
inclusive, hereof.


                                       13






                                   ARTICLE VI

                   LIMITATIONS ON TRANSACTIONS; SUBORDINATION

          Section 6.1 Limitations on Transactions.

     So long as any Trust Preferred Securities remain outstanding, if (i) there
shall have occurred any Event of Default under the Indenture or any event of
which the Guarantor has actual knowledge that (a) with the giving of notice or
the lapse of time or both, would constitute an Event of Default under the
Indenture and (b) in respect of which the Guarantor shall not have taken
reasonable steps to cure, (ii) there shall be a Guarantee Event of Default or
(iii) the Guarantor shall have given notice of its election of an Extension
Period as provided in the certificate evidencing the Subordinated Debt
Securities and shall not have rescinded such notice, or such Extension Period or
any extension thereof shall be continuing, then the Guarantor shall not (x)
declare or pay any dividends or distributions on, or redeem, purchase, acquire
or make a liquidation payment with respect to, any of the Guarantor's capital
stock or (y) make any payment of principal, interest or premium, if any, on or
repay, repurchase or redeem any debt securities of the Guarantor that rank pari
passu with or junior in interest to the Subordinated Debt Securities or make any
guarantee payments with respect to any guarantee by the Guarantor of the debt
securities of any subsidiary of the Guarantor if such guarantee ranks on a
parity with or junior in interest to the Subordinated Debt Securities (other
than (a) any dividend, redemption, liquidation, interest, principal or guarantee
payment by the Guarantor where the payment is made by way of securities
(including capital stock) that rank pari passu with or junior to the securities
on which such dividend, redemption, interest, principal or guarantee payment is
being made, (b) any declaration of a dividend in connection with the Guarantor's
shareholders' rights plan or any successor to such plan, or the issuance of
capital stock of any class or series under any such plan in the future, or the
redemption or repurchase of any such rights pursuant thereto, (c) payments under
this Guarantee, any other similar guarantee by the Guarantor in respect of Trust
Preferred Securities issued by a trust holding Subordinated Debt Securities
issued under the Indenture, (d) repurchases, redemptions or other acquisitions
of capital stock in connection with any benefit plans or other similar
arrangements with or for the benefit of its employees, officers, directors,
consultants or advisors of the Guarantor or any of its subsidiaries, (e) as a
result of a reclassification of the Guarantor's capital stock or the exchange or
conversion of one series of class of the Guarantor's capital stock for another
series or class of the Guarantor's capital stock or (f) the purchase of
fractional interests in shares of the Guarantor's capital stock pursuant to the
conversion or exchange provisions of such capital stock or the security being
converted or exchanged).

          Section 6.2 Subordination.

     This Guarantee will constitute an unsecured obligation of the Guarantor and
will rank (i) subordinate and junior in right of payment to all other
liabilities of the Guarantor, including the Subordinated Debt Securities, except
those obligations or liabilities made pari passu or subordinate by their terms,
(ii) pari passu with the most senior preferred or preference stock now or
hereafter issued by the Guarantor and with any guarantee now or


                                       14






later issued by the Guarantor in respect of any preferred or preference stock of
any Affiliate of the Guarantor, and (iii) senior to all common stock of the
Guarantor.

                                   ARTICLE VII

                                   TERMINATION

          Section 7.1 Termination.

     This Guarantee shall terminate upon:

          (a) full payment of the Redemption Price of all Trust Preferred
     Securities,

          (b) distribution of the Subordinated Debt Securities to the Holders in
     exchange for all the outstanding Trust Preferred Securities, or

          (c) full payment of the amounts payable in accordance with the Trust
     Agreement upon liquidation of the Trust.

Notwithstanding the foregoing, this Guarantee will continue to be effective or
will be reinstated, as the case may be, if at any time any Holder must restore
payment of any sums paid under the Trust Preferred Securities or under this
Guarantee.

                                  ARTICLE VIII

                                 INDEMNIFICATION

          Section 8.1 Exculpation.

          (a) No Indemnified Person shall be liable, responsible or accountable
     in damages or otherwise to the Guarantor or any Covered Person for any
     loss, damage, liability, expense or claim incurred by reason of any act or
     omission performed or omitted by such Indemnified Person in good faith in
     accordance with this Guarantee and in a manner that such Indemnified Person
     reasonably believed to be within the scope of the authority conferred on
     such Indemnified Person by this Guarantee or by law, except that an
     Indemnified Person shall be liable for any such loss, damage or claim
     incurred by reason of such Indemnified Person's negligence or willful
     misconduct with respect to such acts or omissions.

          (b) An Indemnified Person shall be fully protected in relying in good
     faith upon the records of the Guarantor and upon such information,
     opinions, reports or statements presented to the Guarantor by any Person as
     to matters the Indemnified Person reasonably believes are within such other
     Person's professional or expert competence including information, opinions,
     reports or statements as to the value and amount of the assets,
     liabilities, profits, losses, or any other facts pertinent to the existence
     and amount of assets from which Distributions to Holders might properly be
     paid.


                                       15






          Section 8.2 Compensation and Indemnity.

          (a) The Guarantor shall pay to the Guarantee Trustee from time to time
     reasonable compensation for its services. The Guarantee Trustee's
     compensation shall not be limited by any law on compensation of a trustee
     of an express trust. The Guarantor shall reimburse the Guarantee Trustee
     upon request for all reasonable out-of-pocket expenses incurred by it. Such
     expenses shall include the reasonable compensation and expenses of the
     Guarantee Trustee's agents and counsel.

          (b) The Guarantor shall indemnify each of the Indemnified Persons
     (including the cost of defending itself) against any loss, liability or
     expense incurred by it except as set forth in the next paragraph in the
     performance of its duties under this Guarantee. An Indemnified Person shall
     notify the Guarantor promptly of any claim for which it may seek indemnity.
     The Guarantor shall defend the claim and the Indemnified Person shall
     cooperate in the defense. The Guarantor need not pay for any settlement
     made without its consent, which consent shall not be unreasonably withheld.

          (c) The Guarantor need not reimburse any expense or indemnify against
     any loss or liability incurred by an Indemnified Person through such
     Indemnified Person's negligence, bad faith or willful misconduct.

                                   ARTICLE IX

                                  MISCELLANEOUS

          Section 9.1 Successors and Assigns.

     All guarantees and agreements contained in this Guarantee shall bind the
successors, assigns, receivers, trustees and representatives of the Guarantor
and shall inure to the benefit of the Guarantee Trustee, any Successor Guarantee
Trustee and the Holders of the Trust Preferred Securities then outstanding.
Except in connection with a consolidation, merger, sale or conveyance involving
the Guarantor that is permitted by Article - of the Indenture and pursuant to
which the successor or assignee agrees in writing to perform the Guarantor's
obligations hereunder, the Guarantor shall not assign its obligations hereunder.

          Section 9.2 Amendments.

     Except with respect to any changes that do not materially adversely affect
the rights of the Holders (in which case no consent of the Holders will be
required), this Guarantee may not be amended without the prior approval of the
Holders of at least a Majority in Liquidation Amount of the Trust Preferred
Securities. The provisions of Section 11.2 of the Trust Agreement with respect
to meetings of, and action by written consent of, the Holders apply to the
giving of such approval.


                                       16






          Section 9.3 Notices.

     Any notice or communication by the Guarantor or the Guarantee Trustee to
the other is duly given if in writing and delivered in Person or mailed by
first-class mail:

          (a)  if to the Guarantor:
                 Omnicare, Inc.
                 100 East RiverCenter Boulevard
                 Covington, Kentucky 41011
                 Attention: Cheryl D. Hodges
                            Senior Vice President and Secretary

          (b)  if to the Guarantee Trustee:
                 [          ]
                 [          ]
                 [          ]
                 Attention: Corporate Trust Department

     The Guarantor or the Guarantee Trustee by notice to the other may designate
additional or different addresses for subsequent notices or communications.

     Any notice or communication to a Holder shall be mailed by first-class mail
to the address shown on the books and records of the Trust. Failure to mail a
notice or communication to a Holder or any defect in it shall not affect its
sufficiency with respect to other Holders.

     If a notice or communication is mailed or published in the manner provided
above, within the time prescribed, it is duly given, whether or not the Holder
receives it.

          (c) If the Guarantor mails a notice or communication to Holders, it
     shall mail a copy to the Guarantee Trustee at the same time.

          Section 9.4 Counterparts.

     This Guarantee may be executed in any number of counterparts and by the
parties hereto in separate counterparts, each of which when so executed shall be
deemed to be an original and all of which taken together shall constitute one
and the same agreement.

          Section 9.5 Benefit.

     This Guarantee is solely for the benefit of the Holders and, subject to
Section 3.1(a), is not separately transferable from the Trust Preferred
Securities.

          Section 9.6 Governing Laws.

     THIS GUARANTEE AGREEMENT SHALL BE GOVERNED BY THE LAWS OF THE STATE OF NEW
YORK APPLICABLE TO AGREEMENTS MADE AND


                                       17






TO BE PERFORMED IN SUCH STATE, WITHOUT REGARD TO THE CONFLICT OF LAWS PROVISIONS
THEREOF.


                                       18






     IN WITNESS WHEREOF, the parties hereto have caused this Guarantee to be
duly executed as of the day and year first above written.

                                           OMNICARE, INC.,
                                              as Guarantor


                                           By:
                                              ----------------------------------
                                              Name:
                                              Its:


Attest:


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


                                           [                     ],
                                              as Guarantee Trustee


                                           By:
                                              ----------------------------------
                                              Name:
                                              Its:


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