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                                                                    EXHIBIT 10.7

                              INTERDEBTOR AGREEMENT

          THIS INTERDEBTOR AGREEMENT (this "Agreement") is entered into as of
this 8th day of April 2002, by and between ICN Pharmaceuticals, Inc., a Delaware
corporation ("ICN"), and its wholly-owned subsidiary, Ribapharm Inc.
("Ribapharm").

                                    RECITALS

          WHEREAS, Pursuant to an Offering Memorandum dated July 13, 2001, ICN
sold in a private placement, $400,000,000 aggregate principal amount (and an
additional $125,000,000 aggregate principal amount to cover over-allotments) of
6 1/2% Convertible Subordinated Notes due 2008 (the "Notes");

          WHEREAS, the Notes were issued and sold pursuant to the Purchase
Agreement (the "Purchase Agreement"), dated as of July 13, 2001, among ICN,
Ribapharm, and UBS Warburg LLC (the "Initial Purchaser"), the Indenture (the
"Indenture"), dated as of July 18, 2001, among ICN, Ribapharm and The Bank of
New York, as trustee, and the Registration Rights Agreement (the "Registration
Rights Agreement"), dated as of July 18, 2001 among ICN, Ribapharm, and the
Initial Purchaser;

          WHEREAS, Ribapharm has filed a registration statement to effect the
Ribapharm IPO (as defined in the Indenture);

          WHEREAS, ICN intends to distribute its remaining interest in Ribapharm
in the Ribapharm Spin-Off (as defined in the Indenture);

          WHEREAS, ICN and Ribapharm entered into a letter agreement, dated July
18, 2001 (the "Letter Agreement") to clarify their relationship with respect to
certain provisions of the Notes; and

          WHEREAS, each of ICN and Ribapharm believe that it is in their best
interest and in the best interest of their respective stockholders to amend and
restate the Letter Agreement in its entirety as set forth herein.

          NOW, THEREFORE, in consideration of the foregoing and for other good
and valuable consideration the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

          1.   Primary Obligor. While upon the earlier of a Ribapharm IPO or a
Ribapharm Spin-Off, Ribapharm will become a joint and several obligor of the
Notes, as between ICN and Ribapharm, ICN and Ribapharm agree that ICN shall be
responsible for all payments of principal, premium, if any, interest and any
other payments under the Notes, including

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Ribapharm's obligation to make an offer to repurchase the Notes upon a Change in
Control of Ribapharm or ICN. In the event Ribapharm makes any such payments
under the Notes for any reason, ICN shall promptly reimburse Ribapharm for these
payments. Notwithstanding the foregoing, Ribapharm shall be responsible for the
payment of liquidated damages pursuant to Section 5 of the Registration Rights
Agreement caused by Ribapharm's failure to comply with its obligations to file
and maintain an effective Registration Statement.

          2.   Amendments. This Agreement may not be amended or modified in any
respect except by a written agreement signed by both of the parties hereto and
in accordance with the following:

               a.   This Agreement may be amended or modified on behalf of ICN
                    by a written instrument signed by an authorized officer of
                    ICN.

               b.   (i) Any amendment or modification to this Agreement that
                    does not adversely affect the rights of Ribapharm may be
                    made by a written instrument signed by an authorized officer
                    of Ribapharm; and

                    (ii) any other amendment or modification of this Agreement
                    may be made by a written instrument signed by an authorized
                    officer of Ribapharm only after such amendment or
                    modification has been approved by the affirmative vote of at
                    least a majority of the then outstanding shares of common
                    stock of Ribapharm, par value $0.01 per share ("Ribapharm
                    Common Stock"), excluding any shares of Ribapharm Common
                    Stock then beneficially owned by ICN.

          3.   Severability. If any term, provision, covenant or restriction of
this Agreement is held by a court of competent jurisdiction to be invalid, void
or unenforceable, the remainder of the terms, provisions, covenants and
restrictions of this Agreement shall remain in full force and effect and shall
in no way be affected, impaired or invalidated. It is hereby stipulated and
declared to be the intention of the parties that they would have executed the
remaining terms, provisions, covenants and restrictions without including any of
such which may be hereafter declared invalid, void or unenforceable.

          4.   Successors and Assigns. This Agreement shall be binding upon the
parties hereto and inure to the benefit of the parties hereto and their
respective successors and permitted assigns. Except with respect to a merger of
either party with another person, neither this Agreement nor any of the rights,
interests or obligations hereunder shall be assigned by either party hereto
without the prior written consent of the other party.

          5.   Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original, but all such
counterparts shall together constitute one and the same instrument.

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          6.   Headings. The paragraph headings used in this Agreement are for
convenience only and shall not affect the interpretation of any of the
provisions hereof.

          7.   Definitions. All capitalized terms used but not otherwise defined
herein shall have the meanings ascribed to them in (or by reference in) the
Purchase Agreement, Indenture and Registration Rights Agreement, as applicable.

          6.   Entire Agreement. This Agreement shall constitute the entire
agreement between the parties hereto with respect to the subject matter hereof
and shall supersede all prior agreements and understandings, whether written or
oral, between the parties with respect to such subject matter, including,
without limitation, the Letter Agreement.

          7.   Notices. All notices, requests and demands to or upon the parties
to be effective shall be in writing (or by telex, fax or similar electronic
transfer confirmed in writing) and shall be deemed to have been duly given or
made (i) when delivered by hand or (ii) if given by mail, when deposited in the
mails by certified mail, return receipt requested, or (iii) if by telex, fax or
similar electronic transfer, when sent and receipt has been confirmed, addressed
as follows:

               If to ICN:
                                   ICN Pharmaceuticals, Inc.
                                   3300 Hyland Avenue
                                   Costa Mesa, CA  92626
                                   Attention:  General Counsel
                                   Telecopy:  (714) 641-7206
                                   Telephone:  (714) 545-0100

               If to Ribapharm:
                                   Ribapharm Inc.
                                   3300 Hyland Avenue
                                   Costa Mesa, CA  92626
                                   Attention:  General Counsel
                                   Telecopy:  (714) 641-7233
                                   Telephone:  (714) 545-0100

          The parties hereto may change their addresses and transmission numbers
for notices by notice in the manner provided in this Section.

          6.   CONSENT TO JURISDICTION. THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE

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STATE OF NEW YORK (WITHOUT GIVING EFFECT TO THE CONFLICT OF LAWS PRINCIPLES
THEREOF) AS TO ALL MATTERS, INCLUDING MATTERS OF VALIDITY, CONSTRUCTION, EFFECT,
PERFORMANCE AND REMEDIES.

          7.   WAIVER OF TRIAL BY JURY. ICN AND RIBAPHARM HEREBY WAIVE THEIR
RESPECTIVE RIGHTS TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION BASED UPON OR
ARISING OUT OF THIS AGREEMENT. EACH OF ICN AND RIBAPHARM ACKNOWLEDGES THAT THIS
WAIVER IS A MATERIAL INDUCEMENT TO ENTER INTO A BUSINESS RELATIONSHIP, THAT EACH
HAS RELIED ON THE WAIVER IN ENTERING INTO THIS AGREEMENT AND THAT EACH WILL
CONTINUE TO RELY ON THE WAIVER IN THEIR RELATED FUTURE DEALINGS. EACH OF ICN AND
RIBAPHARM WARRANTS AND REPRESENTS THAT EACH HAS HAD THE OPPORTUNITY OF REVIEWING
THIS JURY WAIVER WITH LEGAL COUNSEL, AND THAT EACH KNOWINGLY AND VOLUNTARILY
WAIVES ITS JURY TRIAL RIGHTS.

          8.   EFFECTIVENESS. THIS AGREEMENT SHALL BECOME EFFECTIVE UPON THE
TIME OF PURCHASE OF THE FIRM SHARES, AS DEFINED IN THE UNDERWRITING AGREEMENT,
BY AND AMONG ICN, RIBAPHARM AND THE UNDERWRITERS NAMED THEREIN RELATING TO THE
RIBAPHARM IPO.

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          IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed by their respective officers as of the date first written
above.

                                              ICN PHARMACEUTICALS, INC.

                                              By:______________________
                                              Name:
                                              Title:


                                              RIBAPHARM INC.

                                              By_______________________:
                                              Name:
                                              Title:

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