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                                                                    EXHIBIT 10.8

               AMENDMENT TO DEBENTURE AND SHARE PURCHASE AGREEMENT

      This AMENDMENT (the "AMENDMENT") to DEBENTURE AND SHARE PURCHASE
AGREEMENT, dated as of February 6, 2004 (the "2004 DEBENTURE PURCHASE
AGREEMENT"), by and among Halsey Drug Co., Inc. (the "COMPANY"), Galen Partners
III, L.P. ("GALEN"), Care Capital Investments II, LP ("CARE"), Essex Woodlands
Health Ventures V, L.P. ("ESSEX", and collectively with Galen and Care, the
"MAJORITY LENDERS"), and other signatories thereto (including, without
limitation, through Joinder Agreements) (collectively with the Majority Lenders,
the "LENDERS"), is dated this 1st day of June, 2004. Capitalized terms used
herein which are not defined herein have the meanings ascribed to them in the
2004 Debenture Purchase Agreement.

      WHEREAS, pursuant to the terms of the 2004 Debenture Purchase Agreement,
the aggregate principal amount of the Debentures cannot exceed $14 million
without the prior written consent of the holders of at least 60% of the
principal amount of the Debentures then held by the Majority Lenders;

      WHEREAS, pursuant to the terms of the 2004 Debenture Purchase Agreement,
no Debenture may be issued after the Termination Date;

      WHEREAS, as of the date of this Amendment, the Company has issued
Debentures in the aggregate principal amount of $14,000,000.00 under the 2004
Debenture Purchase Agreement;

      WHEREAS, the Company proposes to issue additional Debentures, such that
the aggregate principal amount of Debentures to be issued under the 2004
Debenture Purchase Agreement will exceed $14,000,000;

      WHEREAS, the Company anticipates that some Debentures may be issued after
the Termination Date;

      WHEREAS, pursuant to Section 14.1 of the 2004 Debenture Purchase
Agreement, an amendment of any provision of the 2004 Debenture Purchase
Agreement must be in writing and signed by the Company (and the Company's
Independent Committee) and the holders of at least 60% of the principal amount
of the Debentures then held by the Lenders;

      WHEREAS, the Majority Lenders are holders of at least 60% of the principal
amount of Debentures presently held by the Lenders;

      WHEREAS, the Majority Lenders desire to amend the 2004 Debenture Purchase
Agreement as set forth below;

      NOW, THEREFORE, in consideration of the foregoing premises and the mutual
covenants and obligations set forth herein, the parties hereby agree as follows:

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1.    Section 3.1 of the 2004 Debenture Purchase Agreement is hereby deleted in
      its entirety and replaced with the following:

                  "The initial Closing will take place at the offices of St.
            John & Wayne, L.L.C., Two Penn Plaza East, Newark, New Jersey 07105
            simultaneously with the execution of this Agreement, or such other
            place, time and date as shall be mutually agreed to by the Company
            and the Purchasers. The Company and the Purchasers acknowledge and
            agree that the Debentures may be sold by the Company on one or more
            Closing Dates; provided, however, that (i) the aggregate principal
            amount of the Debentures shall not exceed $17,500,000 without the
            prior written consent of the holders of at least 60% of the
            principal amount of the Debentures then held by Capital Investment
            II, LP, Essex Woodlands Health Ventures V, L.P., Galen Partners III,
            L.P. and (ii) that no Debentures shall be issued after the
            Termination Date. Upon the issuance of additional Debentures under
            this Agreement, any additional Purchaser (each an "Additional
            Investor") shall be required to execute a Joinder Agreement, which
            Joinder Agreement shall include the aggregate principal amount of
            the Debentures issued to such Purchaser. Any Additional Investors in
            the Debentures executing a Joinder Agreement shall be deemed a
            "Purchaser" for all purposes of this Agreement. Each issuance to an
            Additional Investor shall be made on the terms and conditions of
            this Agreement."

2.    The Definition of "Termination Date" set forth in Article XX of the 2004
      Debenture Purchase Agreement is hereby deleted in its entirety and
      replaced with the following:

                  "Termination Date" means the earlier of (a) June 30, 2004, or
            (b) the Conversion Event.

3.    The parties hereto agree that, except as expressly modified by this
      Amendment, all provisions of the 2004 Debenture Purchase Agreement shall
      remain in full force and effect.

4.    This Amendment may be executed in any number of counterparts, including by
      facsimile copy, each of which shall be deemed an original, but all of
      which together shall constitute one instrument.

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      IN WITNESS WHEREOF, the parties hereto, intending to be legally bound,
have executed this Amendment on the date written above.

HALSEY DRUG CO., INC.
616 N. North Court, Suite 120
Palatine, IL 60067

  /s/ Andrew D. Reddick
--------------------------------------------
By: Andrew D. Reddick
Its: President and Chief Executive Officer

  /s/ William Sumner
--------------------------------------------
By: William Sumner
Its: Independent Committee Member

  /s/ William Skelly
--------------------------------------------
By: William Skelly
Its: Independent Committee Member

  /s/ Alan Smith
--------------------------------------------
By: Alan Smith
Its: Independent Committee Member

GALEN PARTNERS III, L.P.
By: Claudius, L.L.C., General Partner
610 Fifth Avenue, 5th Fl.
New York, New York  10019

  /s/ Srini Conjeevaram
--------------------------------------------
By: Srini Conjeevaram
Its: General Partner

CARE CAPITAL INVESTMENTS II, LP
By: Care Capital, L.L.C., General Partner
Princeton Overlook One
100 Overlook Center, Suite 102
Princeton, New Jersey 08540

  /s/ David R. Ramsay
--------------------------------------------
By: David R. Ramsay
Its: Authorized Signatory

ESSEX WOODLANDS HEALTH VENTURES V, L.P.
By: Essex Woodlands Health Ventures V, L.L.C.,
its General Partner
190 South LaSalle Street, Suite 2800
Chicago, IL 60603

  /s/ Immanuel Thangaraj
--------------------------------------------
By: Immanuel Thangaraj
Its: Managing Director<PAGE>

                                                                    EXHIBIT 10.9

                 FIRST AMENDMENT TO DEBENTURE PURCHASE AGREEMENT

This FIRST AMENDMENT TO DEBENTURE PURCHASE AGREEMENT (the "AMENDMENT") dated
December 20, 2002, by and among Halsey Drug Co., Inc. (the "COMPANY"), Galen
Partners III, L.P. ("GALEN"), Care Capital Investments II, LP ("CARE"), Essex
Woodlands Health Ventures V, L.P. ("ESSEX") and other signatories thereto (the
"PURCHASE AGREEMENT") is made this 11th day of August, 2003. Capitalized terms
not defined herein shall have the meanings ascribed to them in the Purchase
Agreement.

                                    RECITALS

A.    On December 20, 2002, the Company issued approximately $26,400,000 in
      principal amount of 5% Convertible Senior Secured Debentures due March 31,
      2006 (the "2002 DEBENTURES"), all in accordance with the Purchase
      Agreement;

B.    Section 1.2(b) of the Purchase Agreements allows the Company to issue
      additional 2002 Debentures, provided, however, that (i) the aggregate
      principal amount of the 2002 Debentures does not exceed $35 million and
      (ii) no 2002 Debentures (other than debentures evidencing the payment of
      interest on the 2002 Debentures) are to be issued after August 30, 2003
      (the "TERMINATION DATE")

C.    On May 5, 2003, at the Company's request, the Company received a letter
      executed by each of Galen, Care and Essex (the "MAJORITY 2002
      DEBENTUREHOLDERS") advising that the Majority 2002 Debentureholders would
      provide funding to meet the Company's 2003 capital requirements, up to an
      aggregate amount not to exceed $8.6 million (the "LETTER OF SUPPORT").

D.    It is contemplated that the funding by the Majority 2002 Debentureholders
      under the Letter of Support will continue after the Termination Date

E.    The parties desire to amend the Purchase Agreement to provide for a new
      Termination Date.

      NOW, THEREFORE, in consideration of the foregoing premises and the mutual
covenants and obligations set forth herein, the parties hereby agree as follows:

      1.    The Purchase Agreement, including, without limitation, Section
            1.2(b) and Article XX thereof, is hereby amended to change the
            definition of Termination Date to mean December 31, 2003.

      2.    The parties hereto agree that, expect as expressly modified herein,
            all provisions of the Purchase Agreement shall remain in full force
            and effect.

      3.    This Amendment may be executed in two or more counterparts, each of
            which shall be deemed an original but all of which shall constitute
            the same Amendment.

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      IN WITNESS WHEREOF, the parties have cause this Amendment to be executed
by their respective duly authorized officers a of the date first above written.

HALSEY DRUG CO., INC.

By: /s/ Peter A. Clemens
    ----------------------------------------
    Peter A. Clemens
    Acting Chief Executive Officer

GALEN PARTNERS III, L.P.
By: Claudius, L.L.C., General Partner
610 Fifth Avenue, 5th Fl.
New York, New York  10019

/s/ Srini Conjeevaram
----------------------------------------
By: Srini Conjeevaram
Its: General Partner

GALEN EMPLOYEE FUND III, L.P.
By: Wesson Enterprises, Inc.
610 Fifth Avenue, 5th Floor
New York, New York 10020

/s/ Bruce F. Wesson
----------------------------------------
By: Bruce F. Wesson
Its: General Partner

CARE CAPITAL INVESTMENTS II, LP
By: Care Capital II, LLC, General Partner
Princeton Overlook One
100 Overlook Center, Suite 102
Princeton, New Jersey 08540

/s/ David R. Ramsay
----------------------------------------
By: David R. Ramsay
Its: Authorized Signatory

GALEN PARTNERS INTERNATIONAL, III, L.P.
By: Claudius, L.L.C., General Partner
610 Fifth Avenue, 5th Floor
New York, New York  10020

/s/ Srini Conjeevaram
----------------------------------------
By: Srini Conjeevaram
Its: General Partner

ESSEX WOODLANDS HEALTH VENTURES V, L.P.
By: Essex Woodlands Health Ventures V, L.L.C.,
its General Partner
190 South LaSalle Street, Suite 2800
Chicago, IL 60603

/s/ Immanuel Thangaraj
----------------------------------------
By: Immanuel Thangaraj
Its: Managing Director

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