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                                                                    Exhibit 10.6

                               GUARANTY AGREEMENT

         THIS GUARANTY AGREEMENT (the "Guaranty") is dated as of the 29th day of
February, 2000, between THE PROVIDENT BANK, an Ohio banking corporation
("Provident"), and SOLVAY AMERICA, INC., a Delaware corporation (the
"Guarantor").

                              Preliminary Statement

         Duramed Pharmaceuticals, Inc., a Delaware corporation (the "Borrower"),
has requested from Provident a loan in the sum of Twenty Million and 00/100
Dollars ($20,000,000.00) (the "Loan") for the purpose of financing working
capital and other general corporate purposes related to Borrower's
pharmaceutical business located at 5040 Duramed Drive, Cincinnati, Ohio 45213
(the "Premises"). The Loan will be evidenced by two (2) Promissory Notes in the
aggregate amount of the Loan (collectively, the "Notes") dated the date hereof,
and will be secured by an Open-End Mortgage (the "Mortgage"), an Assignment of
Leases, Rents and Proceeds (the "Assignment of Leases") and the UCC Financing
Statements. All obligations of Borrower to Provident under the Notes, the
Mortgage, the Assignment of Leases and the UCC Financing Statements are
hereinafter collectively referred to as the "Indebtedness."

         NOW, THEREFORE, the parties hereto agree as follows:

         1. To induce Provident to make the Loan, the Guarantor hereby
absolutely and unconditionally guarantees the Indebtedness subject to the other
terms and conditions of this Guaranty. The Guarantor undertakes this guarantee
of the aforementioned payment and performance by Borrower notwithstanding that
any portion of the Indebtedness shall be void or voidable as between the
Borrower and any of its creditors including, without limitation, any bankruptcy
trustee of the Borrower. The liability of the Guarantor shall be limited to a
principal amount of Twenty Million and 00/100 Dollars ($20,000,000.00), plus
interest thereon as provided in the Notes (including Default Interest), and all
costs of collection (including reasonable attorneys' fees) and all expenses
reimbursable pursuant to Section 2 hereof.

         2. This Guaranty is a guarantee of payment and not a guarantee of
collection. Notwithstanding the foregoing, upon Borrower's failure to pay any
portion of the Indebtedness promptly when due, Provident shall first, by written
notice, make demand upon the Borrower, with a copy of such notice to Guarantor,
to pay such portion of the Indebtedness as is then due, unless provision of such
a notice shall be prohibited under Title 11 U.S. Code or successor statute, in
which case such notice shall be deemed to have been given as of the date of
effectiveness of the prohibition of such notice. Within thirty (30) days after
such notice shall have been given or deemed given to Borrower, Provident, at its
sole option, may demand payment from the Guarantor of all or any part of the
Indebtedness then due and owing. In addition, Provident may proceed against the
Guarantor
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(or an additional guarantor, if there be any, or against any one or more of the
foregoing) to collect the Indebtedness, with or without proceeding against the
Borrower, any co-maker or co-surety or co- guarantor, any endorser or any
collateral held as security for the Indebtedness. The Guarantor agrees to
reimburse Provident for all reasonable expenses of any nature whatsoever
including, without limitation, reasonable attorneys' fees, incurred or paid by
Provident in exercising any right, power or remedy against Guarantor conferred
by this Guaranty. Any and all payments upon the Indebtedness made by the
Borrower, Guarantor or any other person, or from the proceeds of any collateral
held as security for the Indebtedness, may be applied by Provident against the
Indebtedness in whatever manner it may determine in its sole discretion. Until
the Indebtedness is paid in full, Guarantor shall not exercise any right of
subrogation with respect to payments made by Guarantor pursuant to this
Guaranty.

         Provident shall forbear from exercising any remedy that it might have
under the Mortgage, the Assignment of Leases, the Environmental Indemnity
Agreement or the UCC Financing Statements on account of any default in payment
by Borrower until it shall have demanded payment from Guarantor of such past due
amount as provided above in this Section 2 and Guarantor's failure to pay in
full such past due amount within two (2) business days of Provident's demand
hereof to Guarantor. The failure of Provident to demand payment of any past due
amount from Guarantor as provided herein on any given occasion shall not impair
or be considered a waiver of any such right or power or a waiver of any such
default by Borrower.

         3. The liability of Guarantor and the rights of Provident under this
Guaranty shall not be impaired or affected in any manner by, and Guarantor
hereby consents in advance to and waives any requirement of notice for, any (a)
disposition, impairment, release, surrender, substitution, or modification of
any collateral securing the Indebtedness or the obligations created by this
Guaranty or any failure to perfect a security interest in any such collateral;
(b) release (including adjudication or discharge in bankruptcy) or settlement
with any person primarily or secondarily liable for the Indebtedness (including,
without limitation, any maker, endorser, guarantor or surety); (c) delay in
enforcement of payment of the Indebtedness or delay in enforcement of this
Guaranty; (d) delay, omission, waiver, or forbearance in exercising any right or
power with respect to the Indebtedness or this Guaranty; (e) defense arising
from the enforceability or validity of the Indebtedness or any part thereof or
the genuineness, enforceability or validity of any agreement relating thereto;
(f) any defenses or counterclaims that the Borrower may assert on the
Indebtedness, including, but not limited to, failure of consideration, breach of
warranty, fraud, payment, statute of frauds, bankruptcy, infancy, statute of
limitations, lender liability, accord and satisfaction and usury; or (g) other
act or omission which might constitute a legal or equitable discharge of
Guarantor. Except such notices as are expressly required hereby, Guarantor
waives presentment, protest, demand for payment, any right of set-off, notice of
dishonor or default, notice of acceptance of this Guaranty, notice of the
incurring of any of the Indebtedness and notice of any other kind in connection
with the Indebtedness or this Guaranty. Notwithstanding the foregoing, during
the time the Indebtedness remains outstanding, Provident will not, without the
prior written consent of Guarantor, which consent shall
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not be unreasonably delayed or withheld, agree to any modification to any
material term or condition of the documents which evidence the Indebtedness.

         4. The Guarantor agrees that in the event of (a) the dissolution or
insolvency of Borrower, (b) the inability of Borrower generally to pay its debts
as they become due, (c) an assignment by Borrower for the benefit of its
creditors, (d) the institution by Borrower of any action or proceeding with
respect to itself under Title 11 U.S. Code or successor statute, or (e) the
institution by another entity of any action or proceeding with respect to
Borrower under Title 11 U.S. Code or successor statute, and continuance of such
proceeding for sixty (60) days without dismissal, and whether or not such event
shall occur at a time when the Indebtedness is not then due and payable, the
Guarantor shall upon demand by Provident pay the Indebtedness to Provident as if
the Indebtedness was then due and payable.

         5. In the event of any demand by Provident for payment by Guarantor of
any amount less than payment in full of the Indebtedness pursuant to Section 2
hereof, Guarantor shall have the option to promptly tender to Provident the full
amount owing under this Guaranty.

                  Upon the payment in full to Provident by Guarantor of all the
Indebtedness, Provident shall (a) endorse and deliver to Guarantor the Notes,
without recourse and without any warranties whatsoever, except that Provident
has good title to such Notes, and (b) execute non-recourse assignments of the
Mortgage, the Assignment of Leases, the Environmental Indemnity Agreement and
the UCC Financing Statements, and Guarantor shall be subrogated to the rights of
Provident in respect of such Indebtedness.

         6. The Guarantor agrees that this Guaranty shall continue to be
effective or be reinstated, as the case may be, if at any time payment, or any
part thereof, of principal, interest or any other amount with respect to the
Indebtedness is rescinded or must otherwise be restored by Provident upon the
bankruptcy or reorganization of Borrower, any other person or otherwise.

         7. The Guarantor shall provide Provident with audited financial
statements of Guarantor for Guarantor's fiscal year within one hundred twenty
(120) days after the end of each such fiscal year. Guarantor shall submit to
Provident within ninety (90) days after each quarter financial statements of
Guarantor that are not audited.

         8. Provident shall not be compelled to resort first to any collateral
for payment of any of the Indebtedness or the obligations created by this
Guaranty but may, at its election, require the obligation to be paid by the
Guarantor, with or without suit.

         9. Guarantor agrees that with respect to any uncured Event of Default
under the Notes, the Mortgage, the Assignment of Leases or the Environmental
Indemnity Agreement, Provident shall have the sole option to declare or not to
declare a default thereunder, or to waive any such default
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from time to time, or to waive the right from time to time to accelerate the
Indebtedness after declaring a default, without in any way affecting its right,
after it does declare a default under the Notes, the Mortgage, the Assignment of
Leases or the Environmental Indemnity Agreement, to require payment from the
Guarantor under this Guaranty. After the declaration of any default by Provident
under the Notes, the Mortgage, the Assignment of Leases or the Environmental
Indemnity Agreement, Provident shall have the sole right to determine whether to
apply payments received from the Borrower toward obligations under the
Indebtedness or any other obligations owing by Borrower to Provident.

         10. This Guaranty shall inure to the benefit of and bind the parties
hereto, their successors and assigns, and their legal representatives or heirs.
Provident may, at its option, assign this Guaranty to any lending institution,
bank holding company, insurance company or the like, which becomes the endorsee
or assignee of any part of the Indebtedness, or who is in possession of or the
bearer of any part of the Indebtedness that is payable to the bearer, and the
Guarantor shall continue to be liable under this Guaranty to such other party to
the extent of such indorsed, assigned, or possessed Indebtedness.

         11. This Guaranty and all the rights and obligations of the parties
thereto shall be governed by the laws of the State of Ohio.

         12. As a specifically bargained inducement for Provident to extend
credit to Borrower (a) THE GUARANTOR HEREBY EXPRESSLY WAIVES THE RIGHT TO TRIAL
BY JURY IN ANY LAWSUIT OR PROCEEDING RELATED TO THIS GUARANTY OR ARISING IN ANY
WAY FROM THE INDEBTEDNESS OR TRANSACTIONS INVOLVING PROVIDENT AND THE BORROWER,
AND (b) THE GUARANTOR HEREBY DESIGNATES ALL COURTS OF RECORD SITTING IN
CINCINNATI, OHIO AND HAVING JURISDICTION OVER THE SUBJECT MATTER, STATE AND
FEDERAL, AS FORUMS WHERE ANY ACTION, SUIT OR PROCEEDING IN RESPECT OF OR ARISING
FROM OR OUT OF THIS GUARANTY, ITS MAKING, VALIDITY OR PERFORMANCE, SHALL BE
PROSECUTED AS TO ALL PARTIES, THEIR PERMITTED SUCCESSORS AND ASSIGNS, AND BY THE
FOREGOING DESIGNATION, THE GUARANTOR CONSENTS TO THE JURISDICTION AND VENUE OF
SUCH COURTS.

         13. The Guarantor warrants that it has the corporate power to execute
this Guaranty, that all the necessary corporate actions have been taken to
permit the Guarantor to give this Guaranty, and that the person executing this
Guaranty is duly empowered to do so on behalf of the Guarantor.

         14. Provident warrants that it has the corporate power to execute this
Guaranty, that all the necessary corporate actions have been taken to permit
Provident to enter into this Guaranty, and that the person executing this
Guaranty is duly empowered to do so on behalf of Provident.
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         15. This Guaranty sets forth the complete agreement of the parties with
respect to the subject matter hereof and expressly supersedes the prior or
contemporaneous representation or agreement.

         16. No modification or amendment of this Guaranty shall be effective
unless in writing, signed by the party against whom enforcement is sought. No
waiver of any term or provision of this Guaranty shall be effective unless in
writing and only for the instance then given.

         17. Any notice or consent required or permitted to be given under this
Guaranty shall be sufficient if made in writing and sent via courier, fax or
certified mail, postage prepaid, and shall be effective when received by the
party to whom sent.

             If to Provident, to:     The Provident Bank
                                      Three East Fourth Street
                                      Second Floor
                                      Cincinnati, Ohio  45202
                                      Attention: Richard M. Sterling
                                                 Vice President
                                      Fax:       (513) 579-2398

             with a copy (which copy
             shall not constitute
             notice) to:              Keating, Muething & Klekamp, P.L.L.
                                      1400 Provident Tower
                                      One East Fourth Street
                                      Cincinnati, Ohio  45202
                                      Attention: Mark J. Weber, Esq.
                                      Fax:       (513) 579-6457

             If to Guarantor, to:     Solvay America, Inc.
                                      33 Richmond Avenue
                                      Houston, Texas  77098
                                      Attention: Vice President/General Counsel
                                      Fax:       (713) 525-7818
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             with a copy (which copy
             shall not constitute
             notice) to:              Solvay Pharmaceuticals, Inc.
                                      901 Sawyer Road
                                      Marietta, Georgia  30062
                                      Attention: Vice President-Law,
                                                 Government and Public Affairs
                                      Fax:       (770) 578-5749

         18. Guarantor agrees that it shall not amend or modify any of the
material terms or provisions of that certain Reimbursement Agreement of even
date herewith between Guarantor and Borrower without the prior written consent
of Provident.

       Remainder of page intentionally left blank. Signature page follows.
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         IN WITNESS WHEREOF, the parties hereto have caused their duly
authorized representatives to execute and deliver this Guaranty Agreement on and
as of the date first above set forth.

                                     THE PROVIDENT BANK



                                     By:
                                        ----------------------------------------
                                     Name:  Richard M. Sterling
                                     Its:   Vice President
                                     Date:
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                                     SOLVAY AMERICA, INC.



                                     By: /s/ Philip Uhrhan
                                        ----------------------------------------
                                     Name:   Philip Uhrhan
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                                     Its:    Vice President, Finance
                                         ---------------------------------------
                                     Date:   February 25, 2000
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