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                                                                   EXHIBIT 10.25

                        PREMIER PURCHASING PARTNERS, L.P.
                AMENDMENT NUMBER 1 TO GROUP PURCHASING AGREEMENT
                              CONTRACT #: PP-MS-045

              PRODUCT/SERVICES CATEGORY: IMPLANTABLE/INFUSION PORTS

  (ADDITION OF PRODUCTS, REVISION TO GUARANTEE OF DELIVERY, EXTENSION OF TERM)

         This Amendment Number 1 ("Amendment"), is entered into effective March
1, 1999 (the "Effective Date"), and shall amend and modify the Group Purchasing
Agreement (Contract #: PP-MS-045) by and between Premier Purchasing Partners, LP
("Purchasing Partners"), and Horizon Medical Products, Inc. ("Seller"), dated
effective March 9, 1998 (the "Agreement"), as follows:

         1. Addition of Products. The Agreement is hereby amended effective as
of the Effective Date to add the Products set forth in Exhibit A hereto. The
price of such Products and other pertinent information concerning such Products
is also set forth in Exhibit A hereto.

         2. Revision of Guarantee of Delivery. Section 6.5 (Guarantee of
Delivery) of the Agreement is hereby amended to read that the Guaranteed
Delivery Time Period is seven (7) days for the Products set forth in Exhibit A
hereto.

         3. Extension of Term. The Agreement is hereby amended effective as of
the Effective Date to extend the term of the agreement through February 28,
2004.

         4. Other Terms and Conditions. All other terms and conditions of the
Agreement shall remain in full force and effect.

         This Agreement is hereby executed as of the Effective Date by the
parties authorized representatives set forth below.


PREMIER PURCHASING PARTNERS, LP.            HORIZON MEDICAL PRODUCTS, INC.
("Purchasing Partners")                       ("Seller")
   By: PREMIER PLANS, INC.,
       Its General Partner

       By:      /s/ LYNN DETLOR             By:      /s/ FRANK DEBARTOLA      
          -----------------------------        -------------------------------

       Printed Name:    Lynn Detlor         Printed Name:   Frank DeBartola
                    -------------------                  ---------------------

       Title:      President P.P.           Title:    V. P. Business Dev.  
             --------------------------           ----------------------------

       By:     /s/ JAMES M. GARVEY          
          ----------------------------

       Printed Name: James M. Garvey        
                    ------------------

       Title:     Chief Operating Officer              
             ------------------------------

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                                    EXHIBIT A

Price Protection: Pricing for the products set forth in this Exhibit A will
remain firm throughout the term of the Agreement. In the event of any
industry-wide price decrease for any Product during the term of the Agreement,
Seller will reduce the price of that Product as set forth in this Exhibit A by
the same percentage reduction as such industry-wide price decrease.

Any request for a price increase must be in writing, accompanied by
justification for the increase, and must be transmitted by Seller to Purchasing
Partners at least ninety (90) days prior to the relevant anniversary of the
effective date of this Amendment. Justification for a price increase must
include information such as general market indices indicating increases in raw
materials, labor costs, or other relevant factors. If the price increase request
is not received by Purchasing Partners at least ninety (90) days prior to the
relevant anniversary of the effective date of this Amendment, the pricing will
be held firm for the subsequent twelve month period. A committee composed of
Premier Member Materials Executives shall decide upon the Seller's request and
shall transmit its decision to Seller in writing. If accepted, price increases
would become effective on the relevant anniversary of the effective date of this
Amendment.

Commitment Requirements: Pricing for the Products set forth in this Exhibit A is
available to all Participating Members.