EXHIBIT 10.26

                             SIXTH ADDENDUM TO LEASE


This Sixth  Addendum To Lease is made and entered into the 24th day of November,
1997,   between  Conifer  Prince  Street   Associates   (Landlord)  and  Patient
Infosystems, Inc. formerly DSMI Corporation (Tenant).


WITNESSETH:  that Tenant  currently  leases and  occupies  approximately  11,397
square  feet of office  space at 46 Prince  Street,  Rochester,  New York  14607
pursuant  to a Lease  Agreement  and  First,  Second,  Third,  Fourth  and Fifth
Addendus To Lease, dated February 22, 1995; August 18, 1995;  November 17, 1995;
March 28, 1996; October 29, 1996 and November 30, 1997, respectively.


WHEREAS, Tenant and Landlord desire to expand Tenant's leased premises by Tenant
leasing additional office space,  consisting of approximately 1,557 square feet,
on the Building's lower level (Expansion Space).


NOW,  THEREFORE,  it is mutually  agreed  upon by Landlord  and Tenant to modify
certain provisions of the Lease as follows:

1.  Effective  February 1, 1998,  Tenant's  lease premises shall be increased to
include  approximately 1,557 rentable square feet of office space located on the
lower level of the  Building.  Therefore,  effective  February 1, 1998  Tenant's
leased premises will consist of approximately 12,954 rentable square feet.


2.  Tenant agrees to pay, Base Rent for its' leased premises, consisting of
 approximately 12,954 square feet as following:

                       Period                        Per Sq.ft.         Monthly
                  Month-to-Month                     Base Rent         Base Rent
                     2/28/98                           $13.50         $14,573.26
                  3/1/98-02/28/99                     $14.00          $15,113.00
                  3/1/99-11/30/99                     $14.50          $15,652.76

3.  Effective  February 1, 1998,  Schedule  A-6 shall  replace  Schedule A-4 and
Tenant's pro rata share of taxes, utilities and insurance will be 42.65%.

4. Prior to Tenant's  occupancy of the Expansion Space,  Landlord shall, at its'
sole cost and expense, complete the Scope of Work, as stated on Exhibit A-6.

Except as modified above,  all other terms and conditions of the Lease Agreement
and First, Second, Third, Fourth and Fifth Addendus To Lease, dated February 22,
1995; August 18, 1995;  November 17, 1995; March 28, 1996;  October 29, 1996 and
November 30, 1997,  respectively,  shall remain  unchanged and in full force and
effect.

Agreed to by:                                        Agreed to by:
PATIENT INFOSYSTEMS, INC.           CONIFER PRINCE STREET ASSOCIATES
formerly DSMI CORPORATION

By:  /s/ Donald A. Carlberg         By:   /s/ Thomas L. Fountain    

Date:   November 24, 1997           Date:    November 25, 1997      
     --------------------------          ---------------------------


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                                  SCHEDULE A-6

                             COMMON AREA MAINTENANCE

                                 ADDITIONAL RENT

                                    UTILITIES

Total Square Footage of Building                     30,375

Square Footage Covered by Lease                      12,954

Tenant's Share Electric                              42.65%

                                                        ADDITIONAL RENT

Heating and Air Conditioning

The heat pump units serving the leased premises shall be individually gauged and
the monthly charges shall be calculated as set forth on the attached and further
explained as follows:

1. The heat pump units serving the lease  premises  shall be identified by model
number.

2. The actual heat pump operating  hours will be recorded for each month (column
3) and  multiplied  by the energy use factor  (column 4)  applicable to the heat
pump model to establish the total energy units (column 5).

3. The  total  energy  units  for all  heat  pumps  is then  added to the  total
auxiliary  usage to establish  the grand total usage and energy cost (total KWH)
for the building.

4. The grand total usage and energy cost is multiplied by the utility  company's
rate per KWH to establish the total cost for kilowatt hours.

5. The total  KWH are  divided  by the total  heat  pump  usage and  charges  to
establish the heat pump hourly rate (column 6).

6. The monthly  tenant  charge is the heat pump hourly  rate  multiplied  by the
total energy units (column 5).

7. Tenant will also pay 42.65% of general usage/common area electric.

                                 ADDITIONAL RENT

                      Real Estate and Insurance Escalation

In  addition  to the  rents  set  forth in the  Lease,  and  heretofore  in this
Schedule, with 1995 as the base year, Tenant shall pay 42.65% of the increase in
real  estate  taxes and other  government  levies in lieu of taxes  (payable  in
October of the  following  year),  and 42.65% of the  increase in  property  and
liability insurance premiums (payable in February of the following year).