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                                                                   EXHIBIT 4.16

                                   [DRAXIS LOGO]


June 14, 2000

PERSONAL & CONFIDENTIAL
Dr. Martin Barkin
54 Old Forest Hill Road
Toronto, Ontario
M5P 2P9

Dear Dr. Barkin:

Further to the Resolution dated April 19, 2000 (the "Resolution"), passed by the
Board of Directors of DRAXIS Health Inc. ("DRAXIS"), a copy of which is attached
to this letter agreement, we are writing to confirm the terms pursuant to which
the Board of Directors of DRAXIS will issue to you non-transferable options
("Options") entitling you to purchase 400,000 Common Shares of DRAXIS. We are
further writing to confirm Section 16(c)(4) and Section 24 of your Employment
Agreement as revised on April 15, 1999 (the "Employment Agreement") will be
deemed to be amended by this letter agreement.

Paragraph 3 of the Resolution specifies that you will enter into a letter
agreement which will confirm that the Options shall be exercisable, in
accordance with the terms of the Stock Option Agreement only so long as you are
in the continuous employment of DRAXIS, notwithstanding anything to the contrary
in your Employment Agreement, except where the cessation of employment results
from a change of control or disability, unless otherwise determined by the Board
of Directors.

In consideration for the grant of the Options set out in the Resolution, you
agree to the following terms:

1.       The Options will vest in accordance with paragraph 2 of the Resolution
         and shall be exercisable by you in accordance with the terms of the
         Stock Option Agreement only so long as you remain in the continuous
         employment of DRAXIS, except where cessation of employment results from
         a change of control or disability, unless otherwise determined by the
         Board of Directors.

                                                                            2/

 DRAXIS HEALTH INC., 6870 Goreway Drive, 2nd Floor, Mississauga, Ontario L4V 1P1
                    Tel: (905) 677-5500 Fax: (905) 677-5502
    SANTE DRAXIS INC., 16751 Trans Canada Highway, Kirkland, Quebec H9H 4J4
                    Tel: (514) 694-8220 Fax: (514) 694-8201

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Martin Barkin
June 14, 2000
Page 2

2.       For clarity, in the event of resignation by you or termination of your
         employment by DRAXIS for any reason, with or without cause (but
         excluding termination due to a change of control or disability) (such
         resignation or termination by DRAXIS collectively referred to hereafter
         as "Termination of Employment") the Options which have not vested as at
         the Termination Date (as defined below) will not vest and those Options
         which have vested may be exercised only in accordance with the terms of
         the Stock Option Plan. Upon Termination of Employment, the Termination
         Date shall be the actual date of your resignation or termination by
         DRAXIS of your employment and shall be deemed not to include the three
         year period referred to in Section 16(c)(4) of the Employment Agreement
         or any other period during which you may be in receipt of or eligible
         to receive payments of any nature in lieu of notice of termination or
         as severance.

3.       In the event of Termination of Employment, for purposes of the Options,
         Section 16(c)(4) of the Employment Agreement shall be deemed to be
         amended as follows:

                  16(c) Termination by DRAXIS Without Cause and Without Notice

                  ...

                  Except as outlined in Section 16(b), if your employment is
                  terminated without cause pursuant to this section, DRAXIS
                  shall:

                  (4)      Permit you to retain and exercise all stock options,
                           Employee Participation Shares and other securities
                           which have vested or accrued during your employment
                           with DRAXIS or which will accrue or vest during the
                           three year period following termination of this
                           Agreement and your employment hereunder, as if you
                           had remained employed for that three year period.
                           Notwithstanding the foregoing, you shall not be
                           entitled to retain or exercise any non-transferable
                           options issued pursuant to the Resolution passed by
                           the Board of Directors, dated April 19, 2000, except
                           in accordance with the terms of the letter agreement
                           dated June 14, 2000.

4.       This letter agreement shall not be applicable to the Options if there
         is a termination of your employment due to a change of control or
         disability, in which case Section 16(d) or Section 16(e), respectively,
         of the Employment Agreement shall be applicable.

5.       This letter agreement shall not apply to any stock options previously
         granted to you by the Board of Directors, but shall be applicable only
         to the Options granted pursuant to paragraph 1 of the Resolution.

                                                                            3/

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Martin Barkin
June 14, 2000
Page 3

6.       Section 24 of the Employment Agreement shall be deemed to be amended by
         this letter agreement so that the entire agreement between the parties
         with respect to the terms and conditions of your employment shall be
         the Employment Agreement, the DRAXIS Code of Ethics and this letter
         agreement. Should there be inconsistency between this letter agreement
         and the Employment Agreement with respect to the grant or exercise of
         the Options, this letter agreement and the intent of the Resolution
         shall prevail.

To signify your agreement with the terms of the grant set out in the Resolution
and the exercise of the Options as outlined above, please execute both copies of
this letter agreement and return one originally executed copy to the
undersigned.

Yours truly,

DRAXIS HEALTH INC.

Per: /s/ Brian King
     ----------------------------------------
     Brian King
     Chairman, Board of Directors

I have read and understand and, having had the opportunity to seek independent
legal advice, I accept the terms outlined above in this letter agreement.

  28/6/00                                   /s/  Martin Barkin
-------------------------                 --------------------------------------
Date                                      Dr. Martin Barkin

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                                     [COPY]
                               DRAXIS HEALTH INC.

         The undersigned being all of the directors of DRAXIS Health Inc. (the
"Corporation") do hereby consent to the following resolutions:

OPTIONS TO MARTIN BARKIN

         On recommendation of the Compensation Committee of the Board of
Directors,

RESOLVED THAT:

1.       Non-transferable options (the "Options") are hereby issued to Dr.
         Martin Barkin (the "Optionee") entitling the Optionee to purchase
         400,000 Common Shares at $3.07, the closing price per Common Share
         quoted on The Toronto Stock Exchange on April 19, 2000;

2.       The Options shall be exercisable for a period of five years, subject to
         the terms of the Stock Option Plan (the "Plan") and a stock option
         agreement (the "Stock Option Agreement") shall be entered into between
         the Corporation and the Optionee providing, in particular, that
         one-third of the options shall become exercisable on the first, second
         and third anniversaries of the date of the grant of the Options and
         providing further that the Options shall become exercisable only so
         long as the Optionee is in the continuous employment of the
         Corporation, except where cessation of employment results from a change
         of control or illness, unless otherwise determined by the Board of
         Directors;

3.       Optionee shall enter into a letter agreement with the Corporation
         confirming that the Options shall be exercisable, in accordance with
         the terms of the Stock Option Agreement only so long as the Optionee is
         in the continuous employment of the Corporation, notwithstanding
         anything to the contrary in the Optionee's Employment Agreement, except
         where cessation of employment results from a change of control or
         illness, unless otherwise determined by the Board of Directors;

4.       There be reserved for issuance upon the exercise of the Options such
         number of Common Shares as would be required to be issued assuming the
         due exercise of all the Options;

5.       Upon due exercise of the Options and upon payment of the exercise price
         for the Common Shares, such Common Shares shall be issued as fully paid
         and non-assessable to the Optionee;


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                                          [COPY]

6.       Upon due exercise of the Options, Montreal Trust Company of Canada, as
         Registrar and Transfer Agent for the Common Shares is hereby authorized
         and directed to countersign, issue, register and deliver to the
         Optionee a certificate or certificates for such Common Shares as are
         hereby issuable;

6.       Any officer or director of the Corporation is hereby authorized and
         directed to execute, under the corporate seal of the Corporation or
         otherwise, stock option agreements to effect the foregoing; and

7.       Any officer or director of the Corporation is hereby authorized and
         directed to execute, under the corporate seal of the Corporation or
         otherwise, and to deliver all such other instruments, agreements and
         documents and to do all such acts and things as in his or her opinion
         may be necessary or desirable in connection with the foregoing.

         DATED this 19th day of April, 2000.


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Martin Barkin                         Leslie L. Dan


-----------------------------------   -------------------------------------
George M. Darnell                     James P. Doherty


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Brian M. King                         Samuel Sarick


-----------------------------------   -------------------------------------
Stewart D. Saxe                       John A. Vivash


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