SECOND AMENDMENT TO
CREDIT AGREEMENT

        THIS SECOND AMENDMENT made as of the 17th day of November, 2003, by and
between BIOANALYTICAL SYSTEMS, INC. ("Borrower") and THE PROVIDENT BANK
("Bank");

W I T N E S S E T H:

        WHEREAS, as of October 29, 2002, the parties hereto entered into a
certain Credit Agreement, as amended (as amended, the “Agreement”); and

        WHEREAS, the parties desire to amend the Agreement to extend the time
period to sell Borrower’s Baltimore real estate, subject to the terms contained
herein;

        NOW, THEREFORE, in consideration of the premises, and the mutual
promises herein contained, the parties agree that the Agreement shall be, and it
hereby is, amended as provided herein and the parties further agree as follows:

PART I.    AMENDATORY PROVISIONS

Section 5.    Covenants

        5.2.        Affirmative Covenants.

          5.2.18    Sale of Real Estate.    Section 5.2.18 of the Agreement is
hereby amended by substituting the following new Section 5.2.18 in lieu of the
existing Section 5.2.18:

          5.2.18    Sale of Real Estate.    Not later than December 31, 2004,
cause the Baltimore, Maryland real estate acquired in the Approved PKL
Acquisition to be sold for fair market value.

PART II.    CONTINUING EFFECT

        Except as expressly modified herein:

        (a)        All terms, conditions, representations, warranties and
covenants contained in the Agreement shall remain the same and shall continue in
full force and effect, interpreted, wherever possible, in a manner consistent
with this Second Amendment; provided, however, in the event of any
irreconcilable inconsistency, this Second Amendment shall control;

        (b)        The representations and warranties contained in the Agreement
shall survive this Second Amendment in their original form as continuing
representations and warranties of Borrower; and

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SECOND AMENDMENT TO CREDIT AGREEMENT PAGE 1

        (c)        Capitalized terms used in this Second Amendment, and not
specifically herein defined, shall have the meanings ascribed to them in the
Agreement.

        In consideration hereof, Borrower represents, warrants, covenants and
agrees that:

        (aa)         Each representation and warranty set forth in the
Agreement, as hereby amended, remains true and correct as of the date hereof in
all material respects, except to the extent that such representation and
warranty is expressly intended to apply solely to an earlier date and except
changes reflecting transactions permitted by the Agreement;

        (bb)        There currently exist no offsets, counterclaims or defenses
to the performance of the Obligations (such offsets, counterclaims or defenses,
if any, being hereby expressly waived);

        (cc)        Except as expressly waived in this Second Amendment, there
has not occurred any Default or Unmatured Default; and

        (dd)        After giving effect to this Second Amendment and any
transactions contemplated hereby, no Default or Unmatured Default is or will be
occasioned hereby or thereby.

        IN WITNESS WHEREOF, Borrower and Bank have caused this Second Amendment
to be executed by their respective officers duly authorized as of the date first
above written.

  “BORROWER”

BIOANALYTICAL SYSTEMS, INC.

By:  /s/ Peter T. Kissinger

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Its:  Chairman & CEO

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“BANK”

THE PROVIDENT BANK

By:  /s/ Jeffrey A. Salesman

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Its:  Vice President

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SECOND AMENDMENT TO CREDIT AGREEMENT PAGE 2

PARTICIPANT’S CONSENT

        The undersigned, the “Participant” under that certain Participation
Agreement dated as of October 29, 2002 between the The Provident Bank (the
“Bank”) and the undersigned, hereby consents to the execution and delivery by
the Bank and Bioanalytical Systems, Inc. of the attached Second Amendment to
Credit Agreement and further consents to the terms contained therein. The
undersigned further agrees that the obligations of the undersigned under the
Participation Agreement are hereby ratified, confirmed and reaffirmed in all
respects.

        IN WITNESS WHEREOF, the undersigned has caused this Consent to be
executed by its officer duly authorized as of the 17th day of November, 2003.

  FIFTH THIRD BANK, INDIANA

By:  /s/ M. Anderson

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Its:  Vice President

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