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                              DRUGABUSE SCIENCES, INC.

                         2000 DIRECTORS' STOCK OPTION PLAN

                      (AS ADOPTED EFFECTIVE _______ __, 2000)

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                                  TABLE OF CONTENTS

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ARTICLE 1.  INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

ARTICLE 2.  ADMINISTRATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
     2.1  Committee Composition. . . . . . . . . . . . . . . . . . . . . . . . . . .1
     2.2  Committee Responsibilities . . . . . . . . . . . . . . . . . . . . . . . .1

ARTICLE 3.  SHARES AVAILABLE FOR GRANTS. . . . . . . . . . . . . . . . . . . . . . .1
     3.1  Basic Limitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
     3.2  Annual Increase in Shares. . . . . . . . . . . . . . . . . . . . . . . . .2
     3.3  Additional Shares. . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

ARTICLE 4.  AUTOMATIC OPTION GRANTS TO NON-EMPLOYEE DIRECTORS. . . . . . . . . . . .2
     4.1  Eligibility. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
     4.2  Initial Grants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
     4.3  Annual Grants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
     4.4  Accelerated Exercisability . . . . . . . . . . . . . . . . . . . . . . . .2
     4.5  Exercise Price . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
     4.6  Term . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
     4.7  Affiliates of Non-Employee Directors . . . . . . . . . . . . . . . . . . .3
     4.8  Stock Option Agreement . . . . . . . . . . . . . . . . . . . . . . . . . .3

ARTICLE 5.  PAYMENT FOR OPTION SHARES. . . . . . . . . . . . . . . . . . . . . . . .3
     5.1  Cash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
     5.2  Surrender of Stock . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
     5.3  Exercise/Sale. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
     5.4  Other Forms of Payment . . . . . . . . . . . . . . . . . . . . . . . . . .4

ARTICLE 6.  PROTECTION AGAINST DILUTION. . . . . . . . . . . . . . . . . . . . . . .4
     6.1  Adjustments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
     6.2  Dissolution or Liquidation . . . . . . . . . . . . . . . . . . . . . . . .4
     9.3  Reorganizations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

ARTICLE 7.  LIMITATION ON RIGHTS . . . . . . . . . . . . . . . . . . . . . . . . . .5
     7.1  Shareholders' Rights . . . . . . . . . . . . . . . . . . . . . . . . . . .5
     7.2  Regulatory Requirements. . . . . . . . . . . . . . . . . . . . . . . . . .5
     7.3  Withholding Taxes. . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

ARTICLE 8.  FUTURE OF THE PLAN . . . . . . . . . . . . . . . . . . . . . . . . . . .5
     8.1  Term of the Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
     8.2  Amendment or Termination . . . . . . . . . . . . . . . . . . . . . . . . .5

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ARTICLE 9.  DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

ARTICLE 10.  EXECUTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
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                              DRUGABUSE SCIENCES, INC.

                         2000 DIRECTORS' STOCK OPTION PLAN

       ARTICLE 1.    INTRODUCTION.

              The Plan was adopted by the Board effective as of the date of
the Company's initial public offering.  The purpose of the Plan is to promote
the long-term success of the Company and the creation of shareholder value by
(a) encouraging Non-Employee Directors to focus on critical long-range
objectives, (b) encouraging the attraction and retention of Non-Employee
Directors with exceptional qualifications and (c) linking Non-Employee
Directors directly to shareholder interests through increased stock
ownership.  The Plan seeks to achieve this purpose by providing for automatic
and non-discretionary grants of Options to Non-Employee Directors.

              The Plan shall be governed by, and construed in accordance
with, the laws of the State of California (except their choice-of-law
provisions).

       ARTICLE 2.    ADMINISTRATION.

              2.1    COMMITTEE COMPOSITION.  The Plan shall be administered
by the Committee.  The Committee shall consist exclusively of two or more
directors of the Company, who shall be appointed by the Board.  In addition,
the composition of the Committee shall satisfy such requirements as the
Securities and Exchange Commission may establish for administrators acting
under plans intended to qualify for exemption under Rule 16b-3 (or its
successor) under the Exchange Act.

              2.2    COMMITTEE RESPONSIBILITIES.  The Committee shall
interpret the Plan and make all decisions relating to the operation of the
Plan.  The Committee may adopt such rules or guidelines as it deems
appropriate to implement the Plan.  The Committee's determinations under the
Plan shall be final and binding on all persons.

       ARTICLE 3.    SHARES AVAILABLE FOR GRANTS.

              3.1    BASIC LIMITATION.  The aggregate number of Common Shares
subject to Options granted under the Plan shall not exceed (a) 200,000 plus
(b) the additional Common Shares described in Sections 3.2 and 3.3.  The
limitations of this Section 3.1 and Section 3.2 shall be subject to
adjustment pursuant to Article 6.

              3.2    ANNUAL INCREASE IN SHARES.  As of January 1 of each
year, commencing with the year 2001, the aggregate number of Common Shares
available for the grant of Options under the Plan shall automatically be
increased by the number necessary to cause the total number of Common Shares
then available to be restored to 200,000.

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              3.3    ADDITIONAL SHARES.  If Options are forfeited or
terminate for any other reason before being exercised, then the Common Shares
subject to such Options shall again become available for the grant of Options
under the Plan.

       ARTICLE 4.    AUTOMATIC OPTION GRANTS TO NON-EMPLOYEE DIRECTORS.

              4.1    ELIGIBILITY.  Only Non-Employee Directors shall be
eligible for the grant of Options under the Plan.

              4.2    INITIAL GRANTS.  Each Non-Employee Director who first
becomes a member of the Board after the date of the Company's initial public
offering shall receive a one-time grant of an Option covering 20,000 Common
Shares.  Such Option shall be granted on the date when such Non-Employee
Director first joins the Board.  Subject to the Non-Employee Director's
continuing service, Options granted under this Section 4.2 shall become
exercisable in equal monthly installments over the 48-month period commencing
on the date of grant, except that all of the first 12 installments shall
become exercisable on the first anniversary of the date of grant.  A
Non-Employee Director who previously was an Employee shall not receive a
grant under this Section 4.2.

              4.3    ANNUAL GRANTS.  Upon the conclusion of each regular
annual meeting of the Company's shareholders held in the year 2001 or
thereafter, each Non-Employee Director who will continue serving as a member
of the Board thereafter shall receive an Option covering 5,000 Common Shares,
except that such Option shall not be granted in the calendar year in which
the same Non-Employee Director received the Option described in Section 4.2.
Subject to the Non-Employee Director's continuing service, Options granted
under this Section 4.3 shall become exercisable in full on the first
anniversary of the date of grant.  A Non-Employee Director who previously was
an Employee shall be eligible to receive grants under this Section 4.3.

              4.4    ACCELERATED EXERCISABILITY.  All Options granted to a
Non-Employee Director under this Article 4 shall also become exercisable in
full in the event of:

                     (a)    The termination of such Non-Employee
       Director's service because of death or total and permanent
       disability; or

                     (b)    A Change in Control with respect to the
       Company, except as provided in the next following sentence.

If the Company and the other party to the transaction constituting a Change
in Control agree that such transaction is to be treated as a "pooling of
interests" for financial reporting purposes, and if such transaction in fact
is so treated, then the acceleration of exercisability shall not occur to the
extent that the Company's independent accountants and such other party's
independent accountants separately determine in good faith that such
acceleration would preclude the use of "pooling of interests" accounting.
Acceleration of exercisability may also be required by Section 6.3.

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              4.5    EXERCISE PRICE.  The Exercise Price under all Options
granted to a Non-Employee Director under this Article 4 shall be equal to
100% of the Fair Market Value of a Common Share on the date of grant, payable
in one of the forms described in Article 5.

              4.6    TERM.  All Options granted to a Non-Employee Director
under this Article 4 shall terminate on the earliest of (a) the 10th
anniversary of the date of grant or (b) the date 12 months after the
termination of such Non-Employee Director's service for any reason.

              4.7    AFFILIATES OF NON-EMPLOYEE DIRECTORS.  The Committee may
provide that the Options that otherwise would be granted to a Non-Employee
Director under this Article 4 shall instead be granted to an affiliate of
such Non-Employee Director.  Such affiliate shall then be deemed to be a
Non-Employee Director for purposes of the Plan, provided that the
service-related vesting and termination provisions pertaining to the Options
shall be applied with regard to the service of the Non-Employee Director.

              4.8    STOCK OPTION AGREEMENT.  Each grant of an Option under
the Plan shall be evidenced by a Stock Option Agreement between the Optionee
and the Company.  Such Option shall be subject to all applicable terms of the
Plan and may be subject to any other terms that are not inconsistent with the
Plan.

       ARTICLE 5.    PAYMENT FOR OPTION SHARES.

              5.1    CASH.  All or any part of the Exercise Price may be paid
in cash or cash equivalents.

              5.2    SURRENDER OF STOCK.  All or any part of the Exercise
Price may be paid by surrendering, or attesting to the ownership of, Common
Shares that are already owned by the Optionee.  Such Common Shares shall be
valued at their Fair Market Value on the date when the new Common Shares are
purchased under the Plan.  The Optionee shall not surrender, or attest to the
ownership of, Common Shares in payment of the Exercise Price if such action
would cause the Company to recognize compensation expense (or additional
compensation expense) with respect to the Option for financial reporting
purposes.

              5.3    EXERCISE/SALE.  All or any part of the Exercise Price
and any withholding taxes may be paid by delivering (on a form prescribed by
the Company) an irrevocable direction to a securities broker approved by the
Company to sell all or part of the Common Shares being purchased under the
Plan and to deliver all or part of the sales proceeds to the Company.

              5.4    OTHER FORMS OF PAYMENT.  At the sole discretion of the
Committee, all or any part of the Exercise Price and any withholding taxes
may be paid in any other form that is consistent with applicable laws,
regulations and rules.

       ARTICLE 6.    PROTECTION AGAINST DILUTION.

              6.1    ADJUSTMENTS.  In the event of a subdivision of the
outstanding Common Shares, a declaration of a dividend payable in Common
Shares or a combination or consolidation of the outstanding Common Shares (by
reclassification or otherwise) into a lesser number of

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Common Shares, corresponding adjustments shall automatically be made in each
of the following:

                     (a)    The number of Options available for future
       grants under Article 3;

                     (b)    The number of Common Shares covered by each
       outstanding Option; or

                     (c)    The Exercise Price under each outstanding
       Option.

In the event of a declaration of an extraordinary dividend payable in a form
other than Common Shares in an amount that has a material effect on the price
of Common Shares, a recapitalization, a spin-off or a similar occurrence, the
Committee shall make such adjustments as it, in its sole discretion, deems
appropriate in one or more of the foregoing.  Except as provided in this
Article 6, an Optionee shall have no rights by reason of any issuance by the
Company of stock of any class or securities convertible into stock of any
class, any subdivision or consolidation of shares of stock of any class, the
payment of any stock dividend or any other increase or decrease in the number
of shares of stock of any class.

              6.2    DISSOLUTION OR LIQUIDATION.  To the extent not
previously exercised, Options shall terminate immediately prior to the
dissolution or liquidation of the Company.

              6.3    REORGANIZATIONS.  In the event that the Company is a
party to a merger or other reorganization, outstanding Options shall be
subject to the agreement of merger or reorganization.  Such agreement shall
provide for (a) the continuation of the outstanding Options by the Company,
if the Company is a surviving corporation, (b) the assumption of the
outstanding Options by the surviving corporation or its parent or subsidiary,
(c) the substitution by the surviving corporation or its parent or subsidiary
of its own options for the outstanding Options, (d) full exercisability and
accelerated expiration of the outstanding Options or (e) settlement of the
full value of the outstanding Options in cash or cash equivalents followed by
cancellation of such Options.

       ARTICLE 7.    LIMITATION ON RIGHTS.

              7.1    SHAREHOLDERS' RIGHTS.  A Optionee shall have no dividend
rights, voting rights or other rights as a shareholder with respect to any
Common Shares covered by his or her Option prior to the time when he or she
becomes entitled to receive such Common Shares by filing a notice of exercise
and paying the Exercise Price.  No adjustment shall be made for cash
dividends or other rights for which the record date is prior to such time,
except as expressly provided in the Plan.

              7.2    REGULATORY REQUIREMENTS.  Any other provision of the
Plan notwithstanding, the obligation of the Company to issue Common Shares
under the Plan shall be subject to all applicable laws, rules and regulations
and such approval by any regulatory body as may be required.  The Company
reserves the right to restrict, in whole or in part, the delivery of Common
Shares pursuant to any Option prior to the satisfaction of all legal
requirements relating

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to the issuance of such Common Shares, to their registration, qualification
or listing or to an exemption from registration, qualification or listing.

              7.3    WITHHOLDING TAXES.  To the extent required by applicable
federal, state, local or foreign law, an Optionee or his or her successor
shall make arrangements satisfactory to the Company for the satisfaction of
any withholding tax obligations that arise in connection with the Plan.  The
Company shall not be required to issue any Common Shares or make any cash
payment under the Plan until such obligations are satisfied.

       ARTICLE 8.    FUTURE OF THE PLAN.

              8.1    TERM OF THE PLAN.  The Plan, as set forth herein, shall
become effective on the date of the Company's initial public offering.  The
Plan shall remain in effect until it is terminated under Section 8.2.

              8.2    AMENDMENT OR TERMINATION.  The Board may, at any time
and for any reason, amend or terminate the Plan.  An amendment of the Plan
shall be subject to the approval of the Company's shareholders only to the
extent required by applicable laws, regulations or rules.  The amendment or
termination of the Plan shall not affect any Option previously granted under
the Plan.  No Options shall be granted under the Plan after the termination
thereof.  The Plan shall terminate automatically 10 years after its adoption
by the Board, unless (a) the Plan is extended by the Board and (b) the
extension is approved within 12 months by a vote of the shareholders of the
Company.

       ARTICLE 9.    DEFINITIONS.

              9.1    "BOARD" means the Company's Board of Directors, as
constituted from time to time.

              9.2    "CHANGE IN CONTROL" means:

                     (a)    The consummation of a merger or consolidation
       of the Company with or into another entity or any other corporate
       reorganization, if persons who were not shareholders of the
       Company immediately prior to such merger, consolidation or other
       reorganization own immediately after such merger, consolidation or
       other reorganization 50% or more of the voting power of the
       outstanding securities of each of (i) the continuing or surviving
       entity and (ii) any direct or indirect parent corporation of such
       continuing or surviving entity;

                     (b)    The sale, transfer or other disposition of
       all or substantially all of the Company's assets;

                     (c)    A change in the composition of the Board, as
       a result of which 50% or fewer of the incumbent directors are
       directors who either (i) had been directors of the Company on the
       date 24 months prior to the date of the event that may constitute
       a Change in Control (the "original directors") or (ii) were
       elected, or nominated for election, to the Board with the
       affirmative votes of at

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       least a majority of the aggregate of the original directors who
       were still in office at the time of the election or nomination
       and the directors whose election or nomination was previously so
       approved; or

                     (d)    Any transaction as a result of which any
       person is the "beneficial owner" (as defined in Rule 13d-3 under
       the Exchange Act), directly or indirectly, of securities of the
       Company representing at least 50% of the total voting power
       represented by the Company's then outstanding voting securities.
       For purposes of this Subsection (d), the term "person" shall have
       the same meaning as when used in sections 13(d) and 14(d) of the
       Exchange Act but shall exclude (i) a trustee or other fiduciary
       holding securities under an employee benefit plan of the Company
       or of a Parent or Subsidiary and (ii) a corporation owned directly
       or indirectly by the shareholders of the Company in substantially
       the same proportions as their ownership of the common stock of the
       Company.

A transaction shall not constitute a Change in Control if its sole purpose is
to change the state of the Company's incorporation or to create a holding
company that will be owned in substantially the same proportions by the
persons who held the Company's securities immediately before such transaction.

              9.3    "CODE" means the Internal Revenue Code of 1986, as
amended.

              9.4    "COMMITTEE" means a committee of the Board, as described
in Article 2.

              9.5    "COMMON SHARE" means one share of the common stock of
the Company.

              9.6    "COMPANY" means DrugAbuse Sciences, Inc., a California
corporation.

              9.7    "EMPLOYEE" means a common-law employee of the Company, a
Parent or a Subsidiary.

              9.8    "EXCHANGE ACT" means the Securities Exchange Act of
1934, as amended.

              9.9    "EXERCISE PRICE" means the amount for which one Common
Share may be purchased upon exercise of such Option, as specified in the
applicable Stock Option Agreement.

              9.10   "FAIR MARKET VALUE" means the market price of Common
Shares, determined by the Committee in good faith on such basis as it deems
appropriate.  Whenever possible, the determination of Fair Market Value by
the Committee shall be based on the prices reported in THE WALL STREET
JOURNAL. Such determination shall be conclusive and binding on all persons.

              9.11   "NON-EMPLOYEE DIRECTOR" means a member of the Board who
is not an Employee.

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              9.12   "OPTION" means an option granted under the Plan and
entitling the holder to purchase Common Shares.  Options do not qualify as
incentive stock options described in section 422(b) of the Code.

              9.13   "OPTIONEE" means an individual or estate who holds an
Option.

              9.14   "PARENT" means any corporation (other than the Company)
in an unbroken chain of corporations ending with the Company, if each of the
corporations other than the Company owns stock possessing 50% or more of the
total combined voting power of all classes of stock in one of the other
corporations in such chain.  A corporation that attains the status of a
Parent on a date after the adoption of the Plan shall be considered a Parent
commencing as of such date.

              9.15   "PLAN" means this DrugAbuse Sciences, Inc. 2000
Directors' Stock Option Plan, as amended from time to time.

              9.16   "STOCK OPTION AGREEMENT" means the agreement between the
Company and an Optionee that contains the terms, conditions and restrictions
pertaining to his or her Option.

              9.17   "SUBSIDIARY" means any corporation (other than the
Company) in an unbroken chain of corporations beginning with the Company, if
each of the corporations other than the last corporation in the unbroken
chain owns stock possessing 50% or more of the total combined voting power of
all classes of stock in one of the other corporations in such chain.  A
corporation that attains the status of a Subsidiary on a date after the
adoption of the Plan shall be considered a Subsidiary commencing as of such
date.

       ARTICLE 10.   EXECUTION.

              To record the adoption of the Plan by the Board on January 13,
2000, the Company has caused its duly authorized officer to execute this
document in the name of the Company.

                                       DRUGABUSE SCIENCES, INC.



                                       By: ________________________________

                                       Title: _____________________________


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