SUPPLEMENTAL AGREEMENT TO EXTEND TIME FOR PAYMENT

EXHIBIT 99.1

SUPPLEMENTAL AGREEMENT

     SUPPLEMENTAL AGREEMENT, dated as of December 5, 2006 (the “Agreement”), by and among MARK H. COLEMAN, M.D., PRABAAL DEY, M.D., MARC A. LOEV, M.D. and LESTER A. ZUCKERMAN, M.D. (such individuals being collectively referred to as the “Members”), CENTER FOR PAIN MANAGEMENT ASC, LLC, a Maryland limited liability company (the “Company”), PAINCARE HOLDINGS, INC., a Florida corporation (“PainCare”), and its wholly-owned subsidiary, PAINCARE SURGERY CENTERS III, INC., a Florida corporation (the “Subsidiary”).

W I T N E S S E T H:

     A. The Parties have executed and delivered an Asset Purchase Agreement, effective as of September 26, 2005 (the “Asset Purchase Agreement”), and various additional documentation and agreements, including, without limitation, a Guaranty, a Promissory Note, and a PainCare Stock Pledge Agreement, each effective as of September 26, 2005, pursuant to which, among other things, the Subsidiary is obligated to pay to the Company the sum of $7,758,750 in principal and interest on or prior to January 3, 2007, and PainCare has guaranteed the prompt payment thereof and pledged certain collateral to secure the payment thereof.

     B. PainCare and Subsidiary have requested an extension of time to make full payment of all amounts due under the Promissory Note, and the Parties have agreed that, in consideration for any such extension, the Purchase Price Consideration under the Asset Purchase Agreement shall be increased by the sum of $300,000.00 in recognition of a part of the increased value of assets transferred to the Subsidiary thereunder.

     NOW, THEREFORE, in consideration of the mutual promises and covenants herein contained and the sum of ten dollars ($10.00) and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties, intending to be legally bound, hereby agree as follows:

     1. Defined Terms. Unless otherwise defined in this Agreement, capitalized terms defined in the Asset Purchase Agreement shall have the same meanings herein as in the Asset Purchase Agreement.

     2. Extension of Time for Payment. Effective as of the date hereof, (a) the date for payment of all amounts due and payable under the Promissory Note shall be extended to April 3, 2007 (with interest thereon continuing until the date of payment), and (b) any breach of, or default under, the Supplemental Note (as defined in Section 3 hereof) shall constitute an Event of Default under the Promissory Note which shall cause

all amounts due under the Promissory Note to be accelerated and to immediately become due and payable on and as of the date of any such breach or default under the Supplemental Note. Except as modified herein, all terms and conditions of the Promissory Note are hereby reaffirmed and confirmed and shall remain in full force and effect.

     3. Consideration for Extension. The Subsidiary shall agree to pay to the Company an additional sum of Three Hundred Thousand Dollars ($300,000) (the “Supplemental Consideration”) and shall concurrently herewith execute and deliver to the Company a promissory note (in the form attached hereto as Exhibit A) in the principal amount of Three Hundred Thousand Dollars in satisfaction thereof (the “Supplemental Note”), which the Parties agree and acknowledge represents a portion of the increased value of the Purchased Assets received by the Subsidiary under the Asset Purchase Agreement, and the Purchase Price Consideration is hereby increased by the Supplemental Consideration (net of any forgiveness under the Supplemental Note), which shall be allocated for tax purposes among the Purchased Assets in proportion to the valuations set forth in Disclosure Sche