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                                                                   EXHIBIT 10.21

                                  AMENDMENT #1
                                       TO
                              EMPLOYMENT AGREEMENT

        THIS AMENDMENT #1 TO EMPLOYMENT AGREEMENT (this "Amendment") is made and
entered into as of the 21st day of June, 2001 (the "Effective Date") by and
between DONALD M. EARHART, an individual ("Employee") and I-FLOW CORPORATION, a
Delaware corporation ("Company").

                                   BACKGROUND

        A. The Company and Employee previously entered into that certain
Employment Agreement dated May 16, 1990 (the "Agreement"). Capitalized terms in
this Amendment and not otherwise defined herein shall have the meanings given
them in the Agreement.

        B. The Company and Employee wish to amend and modify certain provisions
in the Agreement as provided herein and effective as of the Effective Date
hereof, while leaving unchanged all other provisions of the Agreement.

                                    AGREEMENT

        1. DUTIES. In light of Employee's promotions since 1990, the first three
sentences of Section 1.2 of the Agreement are hereby deleted in their entirety
and are replaced with the following sentences:

            DURING THE TERM OF THIS AGREEMENT, THE COMPANY SHALL EMPLOY EMPLOYEE
            AS THE COMPANY'S CHAIRMAN, PRESIDENT AND CHIEF EXECUTIVE OFFICER,
            TOGETHER WITH ANY ADDITIONAL DESIGNATIONS OF TITLE AS THE COMPANY'S
            BOARD OF DIRECTORS, IN ITS DISCRETION, MAY PROVIDE TO EMPLOYEE.

        2. BASE SALARY. In light of Employee's base salary increases since 1990,
the second sentence of Section 2.1 of the Agreement is hereby deleted and is
replaced with the following sentence:

           DURING THE TERM OF THIS AGREEMENT, EMPLOYEE'S BASE SALARY SHALL NOT
           BE REDUCED.

        3. BONUS. To provide greater flexibility to the Company and Employee in
determining the form of payment for any annual bonuses that Employee may earn,
Sections 2.2(b) and 2.2(c) of the Agreement are hereby deleted in their
entirety.

        4. VACATION. To provide an additional two (2) weeks of vacation in light
of Employee's more than 11 years of service to the Company, the first sentence
of Section 2.4(a) of the Agreement is hereby deleted and replaced with the
following sentence:

           EMPLOYEE SHALL BE ENTITLED TO SIX (6) WEEKS PAID VACATION DURING EACH
           YEAR OF THIS AGREEMENT.

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        5. AUTOMOBILE ALLOWANCE. To address the effects of inflation since 1990
when Employee's automobile allowance was set at $750 per month plus gasoline
expenses, the text of Section 2.4(b) of the Agreement is hereby deleted in its
entirety and replaced with the following sentence:

            DURING THE TERM OF THIS AGREEMENT, THE COMPANY SHALL PAY EMPLOYEE AN
            AUTOMOBILE EXPENSE ALLOWANCE OF $1,000 PER MONTH, GROSSED UP FOR
            INCOME TAX PURPOSES, AND SHALL REIMBURSE EMPLOYEE FOR ALL GASOLINE
            AND MAINTENANCE EXPENSES INCURRED BY HIM IN OPERATING HIS
            AUTOMOBILE.

        6. TERMINATION WITHOUT CAUSE. To provide Employee with an additional 1
year of severance and continued health insurance benefits in the event of his
termination without cause, and to provide the Company with a deferred payment
option, Section 2.5(b) of the Agreement is hereby deleted in its entirety and
replaced with the following:

            (b) TERMINATION WITHOUT CAUSE. IN THE EVENT EMPLOYEE'S EMPLOYMENT AS
            PROVIDED HEREIN IS TERMINATED BY THE COMPANY WITHOUT CAUSE, OR IN
            THE EVENT EMPLOYEE RESIGNS HIS EMPLOYMENT BECAUSE HIS JOB LOCATION
            IS TRANSFERRED (WITHOUT HIS PRIOR, VOLUNTARY CONSENT) TO A SITE MORE
            THAN THIRTY (30) MILES AWAY FROM HIS CURRENT PLACE OF EMPLOYMENT,
            THE COMPANY SHALL BE OBLIGATED TO PAY AND PROVIDE AND EMPLOYEE SHALL
            BE ENTITLED TO RECEIVE, AS SEVERANCE, THE FOLLOWING PAYMENTS AND
            BENEFITS:

                (i) A CASH PAYMENT EQUAL TO THREE (3) TIMES THE SUM OF (A)
                EMPLOYEE'S ANNUAL SALARY RATE IN EFFECT AT THE TIME OF
                TERMINATION, PLUS (B) THE AVERAGE ANNUAL BONUS EARNED BY
                EMPLOYEE IN THE PREVIOUS THREE FULL FISCAL YEARS; PROVIDED,
                HOWEVER, THAT THE COMPANY MAY, AT ITS ELECTION, PAY TO EMPLOYEE
                ONE-HALF OF SUCH SUM AT THE TIME OF EMPLOYEE'S TERMINATION WITH
                THE REMAINING ONE-HALF TO BE PAID IN EQUAL MONTHLY INSTALLMENTS
                OVER THE 24 MONTHS IMMEDIATELY FOLLOWING THE DATE OF
                TERMINATION;

                (II) ANY BONUS, OR RELEVANT PRO RATA PORTION THEREOF, EARNED BY
                EMPLOYEE FOR THE FISCAL YEAR IN WHICH THE TERMINATION OCCURS,
                TOGETHER WITH ANY AND ALL DEFERRED AND UNPAID BONUS AMOUNTS
                EARNED BY EMPLOYEE PRIOR TO THE EFFECTIVE DATE OF THIS AMENDMENT
                WHICH WERE SUBJECT TO THE DEFERRED PAYMENT PROVISIONS OF (OLD)
                SECTIONS 2.2(B) AND 2.2(C) OF THIS AGREEMENT;

                (III) FOR THE 36-MONTH PERIOD FOLLOWING EMPLOYEE'S TERMINATION
                WITHOUT CAUSE, EMPLOYEE SHALL BE ENTITLED TO CONTINUE TO
                PARTICIPATE AT THE COMPANY'S EXPENSE IN THE GROUP MEDICAL
                INSURANCE PROGRAMS (INCLUDING HEALTH, DRUG, DENTAL, AND VISION
                INSURANCE) WHICH HAD BEEN MADE AVAILABLE TO HIM (INCLUDING HIS
                FAMILY) BEFORE HIS TERMINATION (OR A SUBSTANTIVELY EQUIVALENT
                PROGRAM). THE PROGRAMS SHALL BE CONTINUED IN THE SAME WAY AND AT
                THE SAME LEVEL AS IMMEDIATELY PRIOR TO EMPLOYEE'S TERMINATION
                WITHOUT CAUSE. EMPLOYEE'S PARTICIPATION IN

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                SUCH GROUP MEDICAL INSURANCE PROGRAMS SHALL BE TERMINATED PRIOR
                TO THE 36-MONTH ANNIVERSARY OF EMPLOYEE'S TERMINATION IF AND
                WHEN EMPLOYEE RECEIVES GROUP MEDICAL INSURANCE BENEFITS AS A
                RESULT OF CONCURRENT COVERAGE THROUGH ANOTHER EMPLOYER'S
                PROGRAM; AND

                (IV) EMPLOYEE'S UNVESTED STOCK OPTIONS WHICH ARE OUTSTANDING
                SHALL IMMEDIATELY BECOME FULLY VESTED AND EXERCISABLE, AND ALL
                OF EMPLOYEE'S STOCK OPTIONS SHALL REMAIN EXERCISABLE FOR THEIR
                REMAINING TERM.

Nothwithstanding the foregoing or anything in this Amendment or the Agreement,
Employee shall be entitled to receive whatever additional severance pay and
other benefits, if any, for which he may qualify according to the terms of the
"Agreement Re: Change in Control" entered into as of June 21, 2001 between the
Company and Employee.

        7. CHANGE IN CONTROL. In light of the Agreement Re: Change in Control
entered into between the Company and Employee, Section 2.6 of the Agreement is
deleted in its entirety and references to Section 2.6 found in Section 2.7 of
the Agreement shall be deemed references to the Agreement Re: Change in Control
between the parties.

        8. NOTICES. Employee's address for notices has been changed to 12 Via
Giada, Newport Coast, California 92657.

        9. NO OTHER CHANGES. Except as otherwise set forth in this Agreement,
all terms and provisions of the Agreement remain unchanged and in full force and
effect.

        IN WITNESS WHEREOF, the parties hereto have entered into this Amendment
as of the Effective Date.

I-FLOW CORPORATION                             DONALD M. EARHART

By:                                            By:
    -----------------------------------            -----------------------------
    James J. Dal Porto                             Donald M. Earhart
    Executive VP, COO

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                                                                   EXHIBIT 10.22

                                 PROMISSORY NOTE

$150,000.00                                                       JUNE 15, 2001
                                                         LAKE FOREST, CALIFORNIA

        For value received, Donald M. Earhart ("Borrower") promises to pay to
the order of I-Flow Corporation ("I-Flow"), or to such other person as I-Flow
may from time to time designate, the principal sum of $150,000.00, together with
interest on the outstanding balance which shall accrue at the annual simple rate
of 5.58 percent. This promissory note (this "Note") commences on June 15, 2001
(the "Commencement Date") and all obligations set forth herein are measured from
this date.

        1. Payments. This Note is payable in biweekly payments of $753.38,
principal and interest, with the first payment due on June 29, 2001. All
principal and interest shall be fully repaid no later than 10 years after the
Commencement Date.

        2. Interest Payments; Usury. Any interest not paid when due shall be
added on to the principal sum owing, and shall accrue interest as principal from
such time onwards; provided, however, that in no contingency or event
whatsoever, whether by reason of advancement of the proceeds hereof,
acceleration of maturity of the unpaid principal balance hereof, or otherwise,
will the amount paid or agreed to be paid to I-Flow exceed the highest lawful
rate permissible under applicable usury laws. If, from any circumstances
whatsoever, fulfillment of any provision of this Note at the time performance of
such provision is due, involves exceeding the limit of validity prescribed by
law which a court of competent jurisdiction may deem applicable hereto, then the
obligation to be fulfilled will be reduced to the limit of such validity.
Furthermore, if, from any circumstances whatsoever, I-Flow ever receives as
interest an amount which would exceed the highest lawful rate, the amount which
would be excessive interest will be applied to the reduction of the unpaid
principal balance due hereunder and not to the payment of interest.

        3. Acceleration. If there is any default in the payment of any
installment of principal or interest of this Note, or if Borrower's employment
with I-Flow is terminated for any reason, I-Flow shall have the option to
declare the entire remaining unpaid balance of this Note due and payable at
once.

        4. Place of Performance. All payments and performance of the obligations
under this Note shall be made at I-Flow's office in Lake Forest, California or
such other place as I-Flow may from time to time designate.

        5. Notice. Presentment, demand, protest, notice of protest, dishonor and
nonpayment of this Note and all notices of every kind are hereby waived by
Borrower.

        6. No Waiver. No delay or omission on the part of I-Flow in exercising
any right hereunder shall operate as a waiver of such right or of any other
right under this Note.

        7. Governing Law. This Note shall be governed and interpreted under the
internal laws of the State of California

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        8. Payment. In the event that Borrower's employment with I-Flow is
terminated for any reason and I-Flow declares the entire remaining unpaid
balance of this Note due and payable pursuant to Section 3 hereof, I-Flow shall
have the right to offset any sums payable to Borrower in connection with such
termination, including, but not limited to, a severance payment, by an amount
equal to the remaining unpaid balance under this Note.

        9. Fees and Expenses. In the event that an action is brought by a party
hereto in order to enforce or interpret the terms of this Note, the prevailing
party will be entitled to recover, in addition to any other remedy or relief
that is available to such party, reimbursement for actual costs and expenses
incurred in connection therewith, including, without limitation, actual
attorneys' fees.

        IN WITNESS WHEREOF, the undersigned has caused this Note to be executed
as of the date first written above.

                                               BORROWER

                                               ---------------------------------
                                               Donald M. Earhart

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