Exhibit 10.8

REVOLVING CREDIT NOTE MODIFICATION AGREEMENT

THIS REVOLVING CREDIT NOTE MODIFICATION AGREEMENT (the “Amendment”) is dated as
of May 15, 2008, between ACCENTIA BIOPHARMACEUTICALS, INC., a Florida
corporation (herein called the “Borrower”), and SOUTHWEST BANK OF ST. LOUIS, a
Missouri banking corporation, successor by merger to Missouri State Bank and
Trust Company, a Missouri banking corporation (herein called the “Lender”).

WHEREAS, Borrower and Lender entered into a Revolving Credit Agreement dated
December 30, 2005, as amended (the “Credit Agreement”), pursuant to which
Borrower executed and delivered its Revolving Credit Note originally in the
amount of Three Million and no/100 Dollars ($3,000,000), which note was amended
by that certain Revolving Credit Note Modification Agreement, dated March 29,
2006, to increase the principal amount available for borrowing to Four Million
and No/100 Dollars ($4,000,000) (the “Revolving Credit Note”) and that certain
Revolving Credit Note Modification Agreement, dated January 15, 2007, which
extends the maturity date of the Revolving Credit Note to January 15, 2008, and
that certain Revolving Credit Note Modification Agreement, dated January 15,
2008, which extends the maturity date of the Revolving Credit Note to March 31,
2008, and that certain Revolving Credit Note Modification Agreement, dated
January 15, 2008, which extends the maturity date of the Revolving Credit Note
to May 15, 2008; and

WHEREAS, the Revolving Credit Note matures on May 15, 2008, and lender has not
demanded payment while the parties seek to negotiate an extension, and Borrower
has asked Lender to extend the maturity thereof to July 15, 2008, and to
increase the amount available for borrowing under the Credit Agreement to Four
Million Eighty-Five Thousand and no/100 Dollars ($4,085,000); and

WHEREAS, Lender has agreed to do so subject to the terms and conditions
contained herein;

NOW, THEREFORE, in consideration of the premises and the mutual covenants and
agreements hereinafter set forth, the parties hereto covenant and agree as
follows:

1. Defined Terms. Terms defined in the Credit Agreement and the Revolving Credit
Note shall have the same meanings when used herein.

2. Amendment to Revolving Credit Note.

A. The Revolving Credit Note is hereby amended, effective as of the date hereof,
to delete all references to “$4,000,000” wherever they may appear and substitute
in lieu thereof the following: “$4,085,000”.

B. The Revolving Credit Note is hereby amended, effective as of the date hereof,
to provide for a maturity date of July 15, 2008 (the “Maturity Date”).

C. Except as hereby amended, all terms and conditions of the Note remain the
same and the Note is in full force and effect.

--------------------------------------------------------------------------------

3. Governing Law. This Amendment shall be governed by and construed in
accordance with the law of the State of Missouri.

4. Counterparts. This Amendment may be executed in any number of counterparts
all of which taken together shall constitute one and the same instrument, and
any of the parties hereto may execute this Amendment by signing any such
counterpart.

5. Ratification. Except as amended hereby the Credit Agreement and the Revolving
Credit Note are in all respects ratified, approved and confirmed.

6. Writing Required. ORAL AGREEMENTS OR COMMITMENTS TO LOAN MONEY, EXTEND CREDIT
OR TO FOREBEAR FROM ENFORCING REPAYMENT OF A DEBT, INCLUDING PROMISES TO EXTEND
OR RENEW SUCH DEBT, ARE NOT ENFORCEABLE. TO PROTECT YOU (BORROWER) AND US
(CREDITOR) FROM MISUNDERSTANDING OR DISAPPOINTMENT, ANY AGREEMENTS WE REACH
COVERING SUCH MATTERS ARE CONTAINED IN THIS WRITING, WHICH IS THE COMPLETE AND
EXCLUSIVE STATEMENT OF THE AGREEMENT BETWEEN US, EXCEPT AS WE MAY LATER AGREE IN
WRITING TO MODIFY IT.

IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly
executed as of the day and year first above written.

 

ACCENTIA BIOPHARMACEUTICALS, INC. BY:  

/S/ FRANCIS E. O’DONNELL, JR.

Name:   Francis E. O’Donnell, Jr. Title:   Chairman and CEO SOUTHWEST BANK OF
ST. LOUIS BY:  

/s/ Scott Z. Larson

Name:   Scott Z. Larson Title:   Senior Vice President

 

2