<PAGE>
                                                                    Exhibit 10.6

                          AMENDMENT TO PROMISSORY NOTE

         THIS AMENDMENT, made and entered into as of July 15, 2003, by and
between Horizon Medical Products, Inc., a Georgia corporation ("Horizon"), and
Roy C. Mallady, Jr. ("Mallady");

         WHEREAS, Mallady has delivered his Promissory Note dated September 28
1995 payable to Horizon in the principal amount of Seventy Seven Thousand Six
Hundred Twelve and 43/100 Dollars ($77,612.43) (the "Note"), as amended by
Amendment to Promissory Note dated September 28, 1996;

         WHEREAS, Horizon has agreed with Mallady to change the payment terms
for the Note as provided herein;

         NOW, THEREFORE, in consideration of Ten Dollars ($10.00) paid and other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties agree to amend the Note, as follows:

          1. The entire unpaid principal of Seventy Seven Thousand Six Hundred
Twelve and 43/100 Dollars ($77,612.43) and all accrued and unpaid interest prior
to the date hereof in the amount of Forty Thousand One Hundred Seventy and
No/100 Dollars ($40,170.00) shall be payable in twelve (12) monthly
installments, commencing on July 15, 2003 and on the 15th day of each month
thereafter until paid in full, according to the amortization schedule attached
hereto and incorporated herein by this reference. Interest shall accrue from the
date hereof on the unpaid principal only at the simple rate of eight percent
(8%) per annum and shall be payable in twelve (12) monthly payments on the same
dates as each monthly payment of principal is payable, as provided in the
attached amortization schedule. The total monthly payments for the two preceding
sentences are reflected in "Combined Note 2" in the attached schedule.

          2. Other than the amendment described above, all other provisions of
the Note shall continue in full force and effect. This amendment shall be
binding upon and inure to the benefit of the parties hereto and their personal
representatives, successors, and assigns.

         WITNESS, the execution of the undersigned effective as of the date
first set forth above.

                                           HORIZON MEDICAL PRODUCTS, INC.



                                           By: /s/ Robert Wenzel
                                              ----------------------------------

                                           Title: President
                                                  ------------------------------


                                           /s/Roy C. Mallady, Jr.
                                           -------------------------------------
                                           Roy C. Mallady, Jr.


<PAGE>


                    Schedule to Amendment to Promissory Note


REPAYMENT OF PRINCIPAL OF $77,612 NOTE DATED 09/26/95.
NOTE 2

<TABLE>
<CAPTION>
                      Principal     Interest      Mo pymt
                      ---------     --------     --------
   <S>           <C>  <C>           <C>          <C>             <C>
                                                                 77,612.00  Principal balance
    7/15/2003    1    6,232.59      517.41       6,750.00        71,379.41
    8/15/2003    2    6,274.14      475.86       6,750.00        65,105.28
    9/15/2003    3    6,315.96      434.04       6,750.00        58,789.31
   10/15/2003    4    6,358.07      391.93       6,750.00        52,431.24
   11/15/2003    5    6,400.46      349.54       6,750.00        46,030.78
   12/15/2003    6    6,443.13      306.87       6,750.00        39,587.65
    1/15/2004    7    6,486.08      263.92       6,750.00        33,101.57
    2/15/2004    8    6,529.32      220.68       6,750.00        26,572.25
    3/15/2004    9    6,572.85      177.15       6,750.00        19,999.40
    4/15/2004   10    6,616.67      133.33       6,750.00        13,382.73
    5/15/2004   11    6,660.78       89.22       6,750.00         6,721.94
    6/15/2004   12    6,721.95       44.81       6,766.76            (0.00)

                     77,612.00    3,404.76
</TABLE>


REPAYMENT OF ACCRUED INTEREST ON NOTE 2.

<TABLE>
<CAPTION>
                          Principal   Interest    Mo pymt
                          ---------   --------   --------
    <S>            <C>    <C>         <C>         <C>            <C>
                                                                 40,170.00  Principal balance
     7/15/2003     1      3,347.50      0.00     3,347.50        36,822.50
     8/15/2003     2      3,347.50      0.00     3,347.50        33,475.00
     9/15/2003     3      3,347.50      0.00     3,347.50        30,127.50
    10/15/2003     4      3,347.50      0.00     3,347.50        26,780.00
    11/15/2003     5      3,347.50      0.00     3,347.50        23,432.50
    12/15/2003     6      3,347.50      0.00     3,347.50        20,085.00
     1/15/2004     7      3,347.50      0.00     3,347.50        16,737.50
     2/15/2004     8      3,347.50      0.00     3,347.50        13,390.00
     3/15/2004     9      3,347.50      0.00     3,347.50        10,042.50
     4/15/2004    10      3,347.50      0.00     3,347.50         6,695.00
     5/15/2004    11      3,347.50      0.00     3,347.50         3,347.50
     6/15/2004    12      3,347.50      0.00     3,347.50             0.00

                         40,170.00      0.00
</TABLE>




<PAGE>


COMBINED NOTE 2

<TABLE>
<CAPTION>
                         Principal     Interest      Mo pymt
                         ---------    ---------     ---------
    <S>          <C>     <C>          <C>           <C>            <C>
                                                                   117,782.00  Principal balance
     7/15/2003    1       9,580.09      517.41      10,097.50      108,201.91
     8/15/2003    2       9,621.64      475.86      10,097.50       98,580.28
     9/15/2003    3       9,663.46      434.04      10,097.50       88,916.81
    10/15/2003    4       9,705.57      391.93      10,097.50       79,211.24
    11/15/2003    5       9,747.96      349.54      10,097.50       69,463.28
    12/15/2003    6       9,790.63      306.87      10,097.50       59,672.65
     1/15/2004    7       9,833.58      263.92      10,097.50       49,839.07
     2/15/2004    8       9,876.62      220.68      10,097.50       39,962.25
     3/15/2004    9       9,920.35      177.15      10,097.50       30,041.90
     4/15/2004   10       9,964.17      133.33      10,097.50       20,077.73
     5/15/2004   11      10,008.28       89.22      10,097.50       10,069.44
     6/15/2004   12      10,069.45       44.81      10,097.50           (0.00)

                        117,782.00    3,404.76
</TABLE>