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                                                                    EXHIBIT 10.1

                                                                  EXECUTION COPY

                        AMENDMENT TO EMPLOYMENT AGREEMENT

     This SECOND AMENDMENT TO EMPLOYMENT AGREEMENT (the "Amendment") is made
this 9th day of July, 2007 between PATRICK T. RYAN (the "Executive") and
POLYMEDICA CORPORATION (the "Company").

                                    RECITALS

     R-1. The Executive and the Company entered into an Employment Agreement
dated October 14, 2005, as amended on July 25, 2006 (the "First Amendment"),
which sets forth the terms of the Executive's employment as Chief Executive
Officer and President of the Company (the "Employment Agreement"); and

     R-2. The Company through its Compensation Committee and its Board of
Directors has determined that it is in Company's interest to modify certain
terms of the Executive's employment, and the Executive has agreed to those
modifications.

     In consideration of the recitals set forth above, the mutual promises
contained in this Amendment and other good and valuable consideration, the
receipt and sufficiency of which are acknowledged by the parties, the Executive
and the Company agree as follows:

     1. Term. The parties hereby agree that the initial term of employment as
set forth in Section 1 of the Employment Agreement is hereby amended such that
the initial term shall continue in effect until March 31, 2010. All other
provisions within Section 1 of the Agreement shall remain in full force and
effect.

     2. Title. The parties hereby acknowledge that pursuant to Section 2(a) of
the Employment Agreement, the Executive's title has been modified from
"President and Chief Executive Officer of the Company" to "Chief Executive
Officer of the Company".


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     3. Base Salary. The parties acknowledge that pursuant to Section 3(a) of
the Employment Agreement (providing for periodic increases in the Executive's
base salary), the Executive's base salary was increased 3% (to $724,594 per
annum) effective April 1, 2007.

     4. Calculation of the Executive's Severance for Certain Terminations - Lump
Sum Payment of Severance.

          a.   The parties hereto agree that Sections 3 and 4 of the First
               Amendment are hereby null and void.

          b.   The parties hereto agree that any severance payment payable to
               the Executive pursuant to Section 7(b)(ii)(C) of the Employment
               Agreement shall be equal to two times the sum of (x) the
               Executive's highest Base Salary during the period the Executive
               was employed by the Company and (y) 150% of Employee's target
               bonus, as established by the Company's Compensation Committee and
               Board of Directors, for that Fiscal Year in which the Executive
               was terminated without Cause or in which the Executive terminated
               his employment for Good Reason, and any severance payment payable
               to the Executive pursuant to Section 7(b)(v)(C) of the Employment
               Agreement shall be equal to 2.99 times the sum of (x) and (y) as
               set forth in this paragraph 4(b).

          c.   In connection with the severance payments set forth in paragraph
               4(b), above, the parties hereto agree that, notwithstanding
               anything to the contrary set forth in Sections 7(b)(ii)(C),
               7(b)(ii)(H), 7(b)(v)(C) and 7(b)(v)(H), in the event the
               Executive is deemed to be a "key employee" with the meaning of
               Code Section 416(i), such severance payments shall be paid to the
               Executive in a single lump sum payment on the first business day
               of the seventh month following the


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               Termination Date, consistent with Sections 7(b)(ii)(H) and
               7(b)(v)(H) therein, or such earlier date as may be in compliance
               with the terms of Code Section 409A or any successor statute,
               regulation and guidance thereto, provided that such earlier
               payment shall not increase the total financial obligation of the
               Company under the Agreement, as amended.

     5. Miscellaneous.

          a.   Any capitalized term not expressly defined in this Amendment
               shall have the meaning ascribed to it in the Employment
               Agreement.

          b.   Except as expressly modified by this Amendment, all terms of the
               Executive's Employment Agreement, including the First Amendment,
               shall remain in full force and effect.

                     [Remainder of Page Intentionally Blank]


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     IN WITNESS WHEREOF, the Company has caused this Amendment to be executed by
its duly authorized officer and the Executive has executed this Amendment to
Employment Agreement as of the day and year first above written.

                                        POLYMEDICA CORPORATION

                                        /s/ William C. Van Vassen
                                        ----------------------------------------
                                        Name: William C. Van Vassen
                                              ----------------------------------
                                        Title: Chair, Compensation Committee
                                               ---------------------------------


                                        PATRICK T. RYAN

                                        /s/ Patrick T. Ryan
                                        ----------------------------------------


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