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                                                                   EXHIBIT 10.13

                             SECURED PROMISSORY NOTE

$3,901,331                                                    December 20, 2002
                                                              Corona, California

1.       Promise to Pay. For good and valuable consideration, the receipt of
which is hereby acknowledged, HALSEY DRUG CO., INC., a New York corporation
("Maker"), promises to pay to WATSON PHARMACEUTICALS, INC., a Nevada corporation
("Watson"), or order (either, the "Holder"), on the Maturity Date (as defined
below), unless sooner paid as provided in Section 4 hereof, the principal sum of
Three Million Nine Hundred and One Thousand Three Hundred Thirty One Dollars
($3,901,331), plus accrued unpaid interest thereon. The outstanding principal
balance of this Note shall bear interest at a variable rate equal to the prime
rate announced from time to time by Bank of America (the "Prime Rate") plus four
and one-half percent (4.5%) per annum (the "Interest Rate") from the date such
principal amount becomes outstanding to the date the principal sum is paid in
full; provided, however, that if this Note is not paid in full on the Maturity
Date, the unpaid balance of the Note shall bear interest therefrom and until
paid at the Default Rate (as defined below). Payments of interest shall be due
on the each March 31, June 30, September 30 and December 31 during the term of
this Note commencing December 31, 2002. All payments under this Note shall be
made to the order of the Holder at 311 Bonnie Circle, Corona, California, 92880,
or such other address as Holder may designate in writing to Maker, in U.S.
dollars, and shall be applied first to accrued unpaid interest, if any, and then
to principal.

2.       Maturity Date. The date that this Note shall mature, and the principal
amount outstanding hereunder, plus accrued unpaid interest thereon and any
charges pertaining thereto, shall become due and payable (the "Maturity Date")
shall be March 31, 2006.

3.       Loan and Security Agreements. Maker and Watson are party to that
certain Loan Agreement, dated as of March 29, 2000, as amended by that certain
Amendment to Loan Agreement dated as of March 31, 2000 and as further amended by
that certain Second Amendment to Loan Agreement dated as of December 20, 2002
(as so amended, the "Loan Agreement"). This Note is being issued pursuant to
said Second Amendment, and it is the intention of the Maker and Watson that the
full and punctual payment and performance of this Note by Maker be secured and
guaranteed by the Company General Security Agreement, the Company Collateral
Assignments, the Stock Pledge Agreement, the Guaranties, the Guarantors Security
Agreement, the Guarantor Collateral Assignments and the Mortgage, as those terms
are defined in the Loan Agreement (the "Security Agreements"). The security
interest granted to Holder under the Security Agreements extends to the proceeds
of any sale or other transfer or disposition of such assets, whether by Maker,
its affiliates, the Holder or any other person, that occurs prior to the payment
in full of this Note. Copies of the Loan Agreement and the Security Agreements
may be obtained from Maker without charge.
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4.       Prepayments. Maker may voluntarily prepay this Note either in whole or
in part without penalty or premium.

5.       Waivers. Maker hereby waives diligence, presentment for payment,
demand, protest, notice of non-payment, notice of dishonor, notice of protest,
and any and all other notices and demands whatsoever. Maker shall remain bound
under this Note until all principal and interest and any other amounts that are
payable hereunder or under the Loan Agreement or the Security Agreements have
been paid in full, notwithstanding any extensions or renewals granted with
respect to this Note or the release of any party liable hereunder or any
security for the payment of this Note. Maker, and any and all endorsers hereof,
also waive the right to plead any and all statutes of limitations as a defense
to any demand on this Note or any and all obligations or liabilities arising out
of or in connection with this Note, the Loan Agreement or the Security
Agreements, to the fullest extent permitted by law.

6.       Events of Default. Any of the following events shall constitute an
event of default by Maker under this Note (an "Event of Default"):

         (a)      the failure of Maker to pay to Holder, on the Maturity Date,
any and all principal amounts due and owing under this Note;

         (b)      the failure of Maker to pay to Holder interest payments when
due; or

         (c)      there occurs any other event or circumstance that constitutes
an "Event of Default" as defined in Section 9.1 of the Loan Agreement.

Upon the occurrence of any Event of Default, as defined hereinabove, at Holder's
option, Holder may declare immediately due and payable, and on any such
declaration there shall become immediately due and payable, the entire unpaid
principal balance of this Note, together with all accrued and unpaid interest
under this Note and any other sums owing at the time of such declaration
pursuant to this Note, the Loan Agreement or the Security Agreements, and Holder
shall be entitled to exercise all rights and remedies available to Holder under
this Note, under the Loan Agreement and the Security Agreements and under
applicable law, all of which rights and remedies shall be cumulative. Without
limiting the generality of the foregoing, upon the occurrence of an Event of
Default, the interest rate at which interest shall accrue on the principal sum
and any other amounts that are due under this Note shall increase to the lower
of (i) the Prime Rate plus six and one-half percent (6.5%) per annum or (ii) the
maximum interest rate permitted under applicable law (the "Default Rate"), until
all such amounts have been paid in full.

7.       No Waiver by Holder. Any delay or omission on the part of Holder to
exercise any of Holder's rights or remedies hereunder, under the Loan Agreement
or the Security Agreements or under applicable law, including, without
limitation, the right to accelerate amounts owing under this Note, shall not be
deemed a waiver of that right or remedy or of any other right or remedy of
Holder in respect thereof. The acceptance by Holder of any payment pursuant to
the terms of this Note which is less than payment in full of all

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amounts due and payable at the time of such payment shall not constitute a
waiver of the right to exercise any of the Holder's rights or remedies under
this Note, the Loan Agreement, the Security Agreements or under applicable law
at that time or at any subsequent time or nullify any prior exercise of any such
rights or remedies without the express written consent of Holder, except as and
to the extent provided to the contrary by applicable law.

8.       Governing Law. This Note shall be governed by and construed
according to and enforced under the internal laws of the State of California
without giving effect to its choice of laws rules.

9.       Enforcement of the Note. Maker agrees that the Superior Court in and
for the County of Orange, California shall have exclusive jurisdiction over any
disputes, between the Maker and Holder and any action, suit or other proceeding
brought by Maker or Holder relating to the interpretation or enforcement of this
Note, and Maker agrees as follows: (a) Maker shall accept and not contest the
personal or subject matter jurisdiction of such Court; (b) Maker shall accept
and not object to or challenge the venue of such Court or assert the doctrine of
forum non conveniens with respect to such Court; (c) Maker shall accept and not
contest the validity or effectiveness of service of process in any such action,
suit or other proceeding by registered or certified first class mail; and (d) TO
THE MAXIMUM EXTENT PERMITTED BY LAW, MAKER WAIVES AND SHALL WAIVE ANY RIGHT TO A
TRIAL BY JURY IN ANY ACTION OR OTHER PROCEEDING BROUGHT WITH RESPECT TO THIS
NOTE OR ITS ENFORCEMENT OR INTERPRETATION. If Maker fails to pay any amounts due
hereunder when due, or if an Event of Default occurs, then Maker shall pay all
costs of enforcement and collection, including, without limitation, reasonable
attorneys' fees and costs incurred by Holder, whether or not enforcement and
collection includes the filing of a lawsuit, and whether or not that lawsuit is
prosecuted to judgment. The costs of enforcement and collection shall be added
to the principal amount of the Note and shall accrue interest at the Default
Rate from the date incurred by Holder to the date paid by Maker.

10.      Binding Nature. The provisions of this Note shall be binding on Maker
and shall inure to the benefit of Holder.

11.      Usury Savings Provisions. In the event Holder receives any sums under
this Note which constitute interest in an amount in excess of that permitted by
any applicable law, then, all such sums constituting interest in excess of that
permitted to be paid under applicable law shall, at Holder's option, either be
credited to the payment of principal owing hereunder or returned to Maker. The
provisions of this Section 11 control the other provisions of this Note and any
other agreement between Maker and Holder.

12.      Severability. If, but only to the extent that, any provision of this
Note shall be invalid or unenforceable, then, such offending provision shall be
deleted from this Note, but only to the extent necessary to preserve the
validity and effectiveness of this Note to the fullest extent permitted by
applicable law.

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13.      Interpretation. No provision of this Note shall be interpreted for or
against Maker or Holder because that person or that person's legal
representative drafted such provision. Unless otherwise indicated elsewhere in
this Note, (a) the term "or" shall not be exclusive, (b) the term "including"
shall mean "including, but not limited to," and (c) the terms "below," "above,"
"herein," "hereof," "hereto," "hereunder" and other terms similar to such terms
shall refer to this Note as a whole and not merely to the specific section,
subsection, paragraph or clause where such terms may appear. The section and
sub-section headings in this Note are included for convenience of reference only
and shall be ignored in the construction or interpretation of this Note.

14.      Relation Back of Note. This Note is issued in accordance with that
certain Second Amendment to Loan Agreement dated as of December 20, 2002,
between Maker and Watson (the "Second Amendment"). Maker and Watson acknowledge
and agree that the principal amount of this Secured Promissory Note represents
the full amount of the Core Products Amount of $3,901,331 (as defined and
provided in the Second Amendment), which was heretofore unsecured, and expressly
intend that Maker's obligations pursuant to this Secured Promissory Note be
added to the obligations of Maker secured by the Security Agreements.

                                                 "MAKER"

                                                 HALSEY DRUG CO., INC.

                                                 ____________________________
                                                 By:  Michael Reicher
                                                 Its: Chief Executive Officer

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