# 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:
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| | 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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| | (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
Its:  Chairman & CEOBANK
THE PROVIDENT BANK
By:  /s/ Jeffrey A. Salesman
Its:  Vice President
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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
Its:  Vice President
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