<PAGE>   1

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 10-Q

(Mark One)

[X]      QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
         EXCHANGE ACT OF 1934.

For the quarterly period ended                    March 31, 2000
                              --------------------------------------------------

[ ]      TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
         EXCHANGE ACT OF 1934

     For the transition period from _________________ to _________________

                        Commission file Number: 0-18338

                               I-Flow Corporation
--------------------------------------------------------------------------------
             (Exact name of registrant as specified in its charter)

          California                                     33-0121984
--------------------------------------------------------------------------------
(State or other jurisdiction of             (I.R.S. Employer Identification No.)
 incorporation or organization)

  20202 Windrow Drive, Lake Forest, CA                           92630
--------------------------------------------------------------------------------
(Address of principal executive offices)                       (Zip Code)

                                 (949) 206-2700
--------------------------------------------------------------------------------
              (Registrant's telephone number, including area code)


--------------------------------------------------------------------------------
              (Former name, former address and former fiscal year,
                         if changed since last report)

         Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days. [ x ] Yes [ ] No

                APPLICABLE ONLY TO ISSUERS INVOLVED IN BANKRUPTCY
                   PROCEEDINGS DURING THE PRECEDING FIVE YEARS

         Indicate by check mark whether the registrant has filed all documents
and reports required to be filed by Sections 12, 13 or 15(d) of the Securities
Exchange Act of 1934 subsequent to the distribution of securities under a plan
confirmed by a court.
                                                                 [ ] Yes  [ ] No

                      APPLICABLE ONLY TO CORPORATE ISSUERS:

         Indicate the number of shares outstanding of each of the issuer's
classes of common stock as of the latest practicable date.

         As of March 31, 2000 there were 14,970,016 shares outstanding of Common
Stock.

<PAGE>   2

                               I-FLOW CORPORATION
                                    FORM 10-Q
                      FOR THE QUARTER ENDED MARCH 31, 2000

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                            Page
                                                                            ----
<S>                                                                         <C>
Part I:    Financial Information

     Item 1.  Financial Statements

     Consolidated Balance Sheets as of March 31, 2000 (Unaudited)
         and December 31, 1999                                                3

     Consolidated Statements of Operations for the  three-month
         periods ended March 31, 2000 and 1999 (Unaudited)                    4

     Consolidated Statements of Cash Flows for the three-month periods
         ended March 31, 2000 and 1999 (Unaudited)                            5

     Notes to Consolidated Financial Statements (Unaudited)                   6

     Item 2.  Management's Discussion and Analysis of Financial Condition
       and Results of Operations                                              8

     Item 3.  Quantitative and Qualitative Disclosures About Market Risk     10

Part II:  Other Information                                                  10

     Signatures                                                              12
</TABLE>

<PAGE>   3

                               I-FLOW CORPORATION
                          CONSOLIDATED BALANCE SHEETS

<TABLE>
<CAPTION>
                                                                  March 31,          December 31,
                                                                    2000                 1999
                                                                ------------         ------------
ASSETS                                                           (Unaudited)
<S>                                                             <C>                  <C>
  CURRENT ASSETS:
    Cash and cash equivalents                                   $  1,490,000         $  3,192,000
    Accounts receivable, net                                       9,728,000            8,748,000
    Inventories, net                                               4,308,000            3,785,000
    Prepaid expenses and other                                       575,000              553,000
    Deferred taxes                                                 2,837,000            2,837,000
                                                                ------------         ------------
       Total current assets                                       18,938,000           19,115,000
                                                                ------------         ------------

    Property, net                                                  3,266,000            2,985,000
    Goodwill and other intangibles, net                            7,204,000            5,846,000
    Notes receivable and other                                       822,000              782,000
    Deferred taxes                                                 3,040,000            3,040,000
                                                                ------------         ------------
TOTAL                                                           $ 33,270,000         $ 31,768,000
                                                                ============         ============

LIABILITIES AND SHAREHOLDERS' EQUITY

CURRENT LIABILITIES:
    Accounts payable                                            $  2,280,000         $  1,800,000
    Accrued payroll and related expenses                           1,489,000            1,526,000
    Income taxes payable                                             607,000              607,000
    Current portion of long-term debt                              1,394,000            1,443,000
    Borrowings under line-of-credit                                  114,000               88,000
    Other liabilities                                                101,000               86,000
                                                                ------------         ------------
       Total current liabilities                                   5,985,000            5,550,000
                                                                ------------         ------------

LONG-TERM DEBT                                                     1,190,000            1,548,000
COMMITMENTS AND CONTINGENCIES

SHAREHOLDERS' EQUITY:
    Preferred stock - no par value; 5,000,000 shares
      authorized; no shares issued and outstanding at
      March 31, 2000 and December 31, 1999, respectively                  --                   --
    Common stock - no par value; 40,000,000 shares
      authorized; 14,970,016 and 14,692,125 shares
      issued and outstanding at March 31, 2000 and
      December 31, 1999, respectively                             40,384,000           39,414,000
    Common stock warrants                                            615,000              615,000
    Cumulative other comprehensive income                             50,000               26,000
    Accumulated deficit                                          (14,954,000)         (15,385,000)
                                                                ------------         ------------
       Net shareholders' equity                                   26,095,000           24,670,000
                                                                ------------         ------------
TOTAL                                                           $ 33,270,000         $ 31,768,000
                                                                ============         ============
</TABLE>


See accompanying notes to consolidated financial statements


                                       3
<PAGE>   4

                               I-FLOW CORPORATION
                     CONSOLIDATED STATEMENTS OF OPERATIONS
                                  (Unaudited)

<TABLE>
<CAPTION>
                                                          Three Months Ended
                                                               March 31,
                                                    -------------------------------
                                                       2000                1999
                                                    -----------         -----------
<S>                                                 <C>                 <C>
Net revenues                                        $ 7,467,000         $ 6,218,000
                                                    -----------         -----------
Costs and expenses:
  Cost of sales                                       2,989,000           2,439,000
  Selling and marketing                               1,222,000           1,067,000
  General and administrative                          2,154,000           1,769,000
  Product development                                   321,000             241,000
                                                    -----------         -----------
    Total costs and expenses                          6,686,000           5,516,000

Operating income                                        781,000             702,000

Interest expense                                        (62,000)           (123,000)
Income taxes                                           (288,000)            (21,000)
                                                    -----------         -----------
Net income                                          $   431,000         $   558,000
                                                    ===========         ===========
Net income per share
     Basic and diluted                              $      0.03         $      0.04
                                                    -----------         -----------
Comprehensive Operations:
     Net income                                     $   431,000         $   558,000
     Foreign currency translation adjustment             50,000              24,000
                                                    -----------         -----------
     Comprehensive income                           $   481,000         $   582,000
                                                    ===========         ===========
</TABLE>


See accompanying notes to consolidated financial statements


                                       4

<PAGE>   5

                               I-FLOW CORPORATION
                      CONSOLIDATED STATEMENTS OF CASH FLOWS
                                   (Unaudited)

<TABLE>
<CAPTION>
                                                                            Three Months Ended
                                                                                 March 31,
                                                                      -------------------------------
                                                                         2000                1999
                                                                      -----------         -----------
<S>                                                                   <C>                 <C>
CASH FLOWS FROM OPERATING ACTIVITIES:

Net income                                                            $   431,000         $   558,000
Adjustments to reconcile net income
 to net cash provided by operations:
  Depreciation and amortization                                           754,000             595,000
  Compensation expense for stock option grants                             56,000
  Change in allowance for doubtful accounts                                (8,000)
Change in inventory obsolescence reserve                                 (150,000)
  Changes in operating assets and liabilities:
    Accounts receivable                                                  (971,000)            188,000
    Inventories                                                          (468,000)           (434,000)
    Prepaid expenses and other                                             74,000              55,000
    Accounts payable, accrued and other liabilities                       (39,000)             94,000
                                                                      -----------         -----------
Net cash provided (used) by operating activities                         (321,000)          1,056,000
                                                                      -----------         -----------

CASH FLOWS FROM INVESTING ACTIVITIES:
  Property acquisitions                                                  (582,000)           (200,000)
  Cash paid for acquisition                                              (853,000)                 --
  Change in other assets                                                 (245,000)           (388,000)
                                                                      -----------         -----------
Net cash used by investing activities                                  (1,680,000)           (588,000)
                                                                      -----------         -----------

CASH FLOWS FROM FINANCING ACTIVITIES:
  Net (repayments) proceeds from line of credit                            16,000            (274,000)
  Proceeds from issuance of notes payable                                 306,000                  --
  Payments on notes payable                                              (252,000)           (417,000)
  Proceeds from exercise of stock options and warrants                    220,000                  --
                                                                      -----------         -----------
Net cash provided (used) by financing activities                          290,000            (691,000)
                                                                      -----------         -----------

Effect of exchange rates on cash                                            8,000              24,000

NET DECREASE IN CASH AND CASH EQUIVALENTS                              (1,703,000)           (199,000)

CASH AND CASH EQUIVALENTS AT BEGINNING OF
  PERIOD                                                                3,192,000             971,000
                                                                      -----------         -----------
CASH AND CASH EQUIVALENTS AT END OF PERIOD                            $ 1,489,000         $   772,000
                                                                      ===========         ===========

SUPPLEMENTAL CASH FLOW INFORMATION:
Interest paid                                                         $    94,000         $   125,000
                                                                      -----------         -----------
Income tax payments                                                   $    61,000         $    12,000
                                                                      -----------         -----------
Preferred stock dividends payable                                     $        --         $    20,000
                                                                      -----------         -----------
Liabilities issued and assumed in connection with acquisition:
  Fair value of assets acquired (including intangibles)               $ 1,911,000
  Cash outflows for business acquisition                                 (853,000)
  Common stock issued                                                    (750,000)
                                                                      -----------
Liabilities issued and assumed                                        $   308,000
                                                                      ===========
</TABLE>


See accompanying notes to consolidated financial statements


                                       5
<PAGE>   6

                               I-FLOW CORPORATION
                   NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

                                   (Unaudited)

1.       BASIS OF PRESENTATION

         The accompanying unaudited consolidated financial statements contain
         all adjustments (consisting only of normal recurring adjustments) that,
         in the opinion of management, are necessary to present fairly the
         financial position of I-Flow Corporation (the Company) at March 31,
         2000 and the results of its operations and its cash flows for the
         three-month periods ended March 31, 2000 and 1999. Certain information
         and footnote disclosures normally included in financial statements have
         been condensed or omitted pursuant to rules and regulations of the
         Securities and Exchange Commission although the Company believes that
         the disclosures in the financial statements are adequate to make the
         information presented not misleading.

         The financial statements included herein should be read in conjunction
         with the financial statements of the Company included in the Company's
         Annual Report on Form 10-K for the year ended December 31, 1999 filed
         with the Securities and Exchange Commission on March 30, 2000.

         Certain amounts previously reported have been reclassified to conform
         with the presentation at March 31, 2000.

2.       INVENTORIES

         Inventories consisted of the following as of March 31, 2000 and
         December 31, 1999:

<TABLE>
<CAPTION>
                                                  March 31,        December 31,
                                                     2000              1999
                                                 -----------       ------------
<S>                                              <C>               <C>
                   Raw Materials                 $ 4,182,000       $ 3,581,000
                   Work in Process                   373,000           164,000
                   Finished Goods                  1,206,000         1,708,000
                   Reserve for Obsolescence       (1,453,000)       (1,668,000)
                                                 -----------       -----------
                   Total                         $ 4,308,000       $ 3,785,000
                                                 ===========       ===========
</TABLE>

3.       EARNINGS PER SHARE

         Basic net income per share is computed using the weighted average
         number of common shares outstanding during the periods presented.

         Diluted net income per share is computed using the weighted average
         number of common and common equivalent shares outstanding during the
         periods presented assuming the conversion of all shares of the
         Company's convertible preferred stock into common stock and the
         exercise of all in-the-money stock options. Common equivalent shares
         have not been included where inclusion would be antidilutive.


                                       6
<PAGE>   7

         The following is a reconciliation between the net income and the number
         of shares used in the basic and diluted net income per share
         calculations:

<TABLE>
<CAPTION>
                                                                     Three Months Ended
                                                                          March 31,
                                                                   -----------------------
           (Amounts in thousands)                                   2000            1999
                                                                   -------        --------
<S>                                                                <C>            <C>
           Net income                                              $   431        $    558
           Less preferred stock dividends                               --              (4)
                                                                   -------        --------
             Net income available to common shareholders           $   431        $    554
                                                                   -------        --------
           Basic net income per  share
              Weighted average number of shares outstanding         14,886          14,099
              Effect of dilutive securities:
                 Preferred stock                                        --             140
                 Stock options                                         897             454
                                                                   -------        --------
           Diluted net income  per share
              Weighted average number of shares outstanding         15,783          14,693
                                                                   -------        --------
</TABLE>

4.       BUSINESS SEGMENTS

         The Company operates in two business segments: manufacturing and
         marketing of medical infusion products and rentals of medical infusion
         pumps.

         Business segment information is as follows for the three-month periods
         ended March 31, 2000 and 1999:

<TABLE>
<CAPTION>
         (Amounts in         Manufacturing
          thousands)         and Marketing      Rentals      Consolidated
                             -------------      -------      ------------
<S>                          <C>                <C>          <C>
         2000
         Revenues                $ 5,271        $ 2,196        $ 7,467
         Operating income            259            522            781
         Assets                   23,243         10,027         33,270

         1999
         Revenues                  4,228          1,990          6,218
         Operating income            292            410            702
         Assets                   15,770          8,549         24,319
</TABLE>

5.       ACQUISITION OF SPINAL SPECIALTIES, INC.

         On January 14, 2000, the Company acquired Spinal Specialties, Inc., a
         designer and manufacturer of custom spinal, epidural and nerve block
         infusion kits based in San Antonio, Texas, for $1.5 million. The
         purchase price consisted of $750,000 in cash and 200,000 shares of
         I-Flow common stock. The acquisition was accounted for under the
         purchase method of accounting and the purchase price has been allocated
         to the net assets acquired and goodwill.


                                       7
<PAGE>   8

ITEM 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
         CONDITION AND RESULTS OF OPERATIONS

         Certain disclosures made by the Company in this report and in other
         reports and statements released by the Company are and will be
         forward-looking in nature, such as comments that express the Company's
         opinions about trends and factors that may impact future operating
         results. Disclosures that use words such as the Company "believes,"
         "anticipates," or "expects" or use similar expressions are intended to
         identify forward-looking statements. Such statements are subject to
         certain risks and uncertainties that could cause actual results to
         differ from those expected. Readers are cautioned not to place undue
         reliance on these forward-looking statements. The Company undertakes no
         obligation to publish revised forward-looking statements to reflect the
         occurrence of unanticipated events. Readers are also urged to carefully
         review and consider the various disclosures made by the Company in this
         report that seek to advise interested parties of the risks and other
         factors that affect the Company's business, as well as in the Company's
         periodic reports on Forms 10-K, 10-Q, and 8-K filed with the Securities
         and Exchange Commission. The risks affecting the Company's business
         include reliance on the success of the home health care industry, the
         ability to penetrate hospital accounts, the health care reimbursement
         system in place now and in the future, competition in the industry,
         demand in foreign countries, customer credit risks, technological
         changes and product availability. Any such forward-looking statements,
         whether made in this report or elsewhere, should be considered in
         context with the various disclosures made by the Company about its
         business.

RESULTS OF OPERATIONS

         Net revenues during the three-month period ended March 31, 2000 were
         $7,467,000 compared to $6,218,000 for the same period in the prior
         year, representing an increase of 20%. In January 2000, the Company
         acquired a new subsidiary, Spinal Specialties, Inc., a designer and
         manufacturer of custom spinal, epidural and nerve block infusion kits
         based in San Antonio, Texas. Revenues generated by Spinal Specialties,
         Inc. of $448,000 were included in net revenues for the three-month
         period ended March 31, 2000. The balance of the revenue increase
         resulted from an approximate $600,000 increase in product sales and an
         approximate $200,000 increase in infusion pump rental revenue.

         In March 1999, the Company entered into an agreement with B. Braun
         Melsungen AG (G.BRN), a world leader in the manufacture and
         distribution of pharmaceuticals and infusion products, to distribute
         I-Flow's elastomeric infusion pumps in Western Europe, Eastern Europe,
         the Middle East, Asia Pacific, South America and Africa. The Company
         also entered into a similar agreement under which B. Braun of America,
         Inc. distributes I-Flow's elastomeric pumps to its full line IV
         solution customers in the United States.

         In May 1999, the Company entered into an agreement with dj Orthopedics
         LLC (formerly DonJoy, a division of Smith & Nephew, Inc.), a leading
         provider of orthopedic braces, to distribute the Company's PainBuster
         pain management system exclusively in the United States and Canada for
         orthopedic surgery applications. I-Flow's PainBuster pain management
         system provides continuous infusion of a non-narcotic, local anesthetic
         directly into the intraoperative site for post-operative pain
         management.

         In June 1999, the Company signed a distribution agreement with Ethicon
         Endo-Surgery, Inc., a Johnson & Johnson Company, under which Ethicon
         Endo-Surgery became the exclusive, worldwide distributor of I-Flow's
         ON-Q Pain Management System for all surgical applications excluding
         orthopedics. The ON-Q Pain Management System infuses non-narcotic local
         anesthetics directly into the intraoperative site, the patient's
         primary source of post-operative pain. This multi-year agreement
         requires Ethicon Endo-Surgery to meet minimum purchase commitments to
         maintain exclusive distribution rights.

         Cost of sales of $2,989,000 were incurred during the three-month period
         ended March 31, 2000, compared to $2,439,000 in the prior year. As a
         percentage of net revenue, cost of sales was relatively unchanged
         compared to the same period in the prior year.


                                       8
<PAGE>   9

         Selling and marketing expenses for the three-month period ended March
         31, 2000 increased over the same period in the prior year by $155,000,
         or 15%, due primarily to the addition of $90,000 in selling expenses
         for Spinal Specialties for the three-month period in 2000. As a percent
         of net revenues, selling and marketing expenses for the three-month
         period ended March 31, 2000 were down by 1% compared to the same period
         in the prior year.

         General and administrative expenses for the three-months ended March
         31, 2000 increased $385,000 or 22% from the same period in the prior
         year. These increases are due primarily to the addition of Spinal
         Specialties for the three-month period in 2000, as well as increased
         personnel costs, insurance costs and various other costs associated
         with the growth in the business.

         Product development expenses for the three-months ended March 31, 2000
         increased over the same period in the prior year by $80,000, or 33%,
         due primarily to increased efforts on the new pain management products.
         The Company will continue to incur product development expenses as it
         continues its efforts to introduce new and improved technology and
         cost-efficient products into the market.

LIQUIDITY AND CAPITAL RESOURCES

         During the three-month period ended March 31, 2000, funds of $321,000
         were used by operating activities consisting of net income of $431,000
         plus non-cash expenses of $652,000 less net changes in operating assets
         and liabilities of $1,404,000. These changes in operating assets and
         liabilities consisted of: (1) an increase in accounts receivable of
         $971,000, (2) an increase in inventories of $468,000, (3) a decrease in
         prepaid expenses and other of $74,000, less (4) a decrease in accounts
         payable, accrued expenses, and other liabilities of $39,000.

         The Company used funds for investing activities during the three-month
         period ended March 31, 2000 aggregating $1,680,000. These expenditures
         consisted of $582,000 for acquiring furniture, fixtures and equipment
         for use in its operations and an increase in other assets of $245,000.
         Additionally, in January 2000, the Company used $853,000 in connection
         with the acquisition of Spinal Specialties, Inc. (see Note 5 of Notes
         to Consolidated Financial Statements).

         During the three-month period ended March 31, 2000, funds of $290,000
         were provided by financing activities consisting primarily of $220,000
         in proceeds from the exercise of stock options. Additionally, the
         Company had proceeds on notes payable net of payments of $54,000 and a
         net increase on the Company's line of credit of $16,000.

         As of March 31, 2000, the Company had cash funds of $1,490,000 and net
         receivables of $9,728,000. Management believes the Company's funds are
         sufficient to provide for its short and long-term projected needs for
         operations. However, the Company may decide to sell additional equity
         or increase its borrowings in order to fund increased product
         development or for other purposes.

YEAR 2000 COMPLIANCE

         The Company did not experience any significant malfunctions or errors
         in its operating or business systems when the date changed from 1999 to
         2000. Based on operations since January 1, 2000, the Company does not
         expect any significant impact to its ongoing business as a result of
         the "Year 2000 issue." However, it is possible that the full impact of
         the date change, which was of concern due to computer programs that use
         two digits instead of four digits to define years, has not been fully
         recognized. For example, it is possible that Year 2000 or similar
         issues such as leap year-related problems may occur with billing,
         payroll, or financial closings at month, quarter or year-end. The
         Company believes that any such problems are likely to be minor and
         correctable. In addition, the Company could still be negatively
         affected if the Year 2000 or similar issues adversely affect its
         customers or suppliers. The Company


                                       9
<PAGE>   10

         currently is not aware of any significant Year 2000 or similar problems
         that have arisen for its customers and suppliers.

         The Company expended less then $150,000 on Year 2000 readiness efforts
         from 1998 to 1999. These efforts included replacing some outdated,
         noncompliant hardware and noncompliant software as well as identifying
         and remediating Year 2000 problems.

ITEM 3.  QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.

FOREIGN CURRENCY

         The Company has a subsidiary operating in Mexico. Accordingly, the
         Company is exposed to transaction gains and losses that could result
         from changes in foreign currency exchange rates. The Company believes
         that this foreign currency market risk is not material.


                           PART II - OTHER INFORMATION

Items 1. - 5.     Not applicable.

Item 6.  Exhibits and Reports on Form 8-K

         (a) Exhibits

<TABLE>
<CAPTION>
     Exhibit No.                                        Exhibit
     -----------                                        -------
<C>                 <S>
           3.1      Restated Articles of Incorporation of the Company (2)

           3.2      Certificate of Amendment to Restated Articles of
                    Incorporation dated June 14, 1991 (3)

           3.3      Certificate of Amendment to Restated Articles of
                    Incorporation dated May 12, 1992 (4)

           3.4      Certificate of Determination covering Company's Series B
                    Preferred Stock filed with the Secretary of State on October
                    5, 1992 (4)

           3.5      Restated Bylaws as of July 22, 1991 of the Company (3)

           4.1      Specimen Common Stock Certificate (4)

           4.2      Warrant Agreement between the Company and American Stock
                    Transfer & Trust Company, as Warrant Agent, dated February
                    13, 1990 (1)

           4.3      Form of Warrant dated July 22, 1996, issued in conjunction
                    with the acquisition of Block Medical, Inc. (5)

          10.1      Employment Agreement with Donald M. Earhart dated May 16,
                    1990 (2)(6) *

          10.2      1987-1988 Incentive Stock Option Plan and Non-Statutory
                    Stock Option Plan Restated as of March 23, 1992 (5)(6) *

          10.3      1992 Non-Employee Director Stock Option Plan (4)(6)

          10.4      License and Transfer Agreement with SoloPak Pharmaceuticals
                    Inc., dated March 6, 1996 (7)

          10.5      1996 Stock Incentive Plan (6)(9) *

          10.6      Agreement for Purchase and Sale of Assets dated as of July
                    3, 1996 by and among I-Flow Corporation, Block Medical, Inc.
                    and Hillenbrand Industries, Inc. (8)
</TABLE>


                                       10
<PAGE>   11

<TABLE>
<C>                 <S>
          10.7      Employment Agreement with James J. Dal Porto dated September
                    6, 1996 (10) *

          10.8      Lease Agreement Between Industrial Developments
                    International, Inc. as Landlord and I-Flow Corporation as
                    Tenant dated April 14, 1997 (11)

          10.9      Agreement and Plan of Merger by and among I-Flow
                    Corporation, I-Flow Subsidiary, Inc., Venture Medical, Inc.,
                    and InfuSystems II, Inc. and the Shareholders of Venture
                    Medical, Inc. and InfuSystems II, Inc. (12)

          10.10     Loan and Security Agreement between Silicon Valley Bank and
                    I-Flow Corporation dated September 28, 1995 (13)

          10.11     Amendment to Loan Agreement between Silicon Valley Bank and
                    I-Flow Corporation dated March 2, 1999 (13)

          10.12     Agreement and Plan of Merger By and Among I-Flow
                    Corporation, Spinal Acquisition Corp., Spinal Specialties,
                    Inc. and the Shareholders of Spinal Specialties, Inc. dated
                    January 13, 2000

          27        Financial Data Schedule
</TABLE>

(1)      Incorporated by reference to exhibit with this title filed with the
         Company's Registration Statement (#33-32263-LA) declared effective
         February 1, 1990.

(2)      Incorporated by reference to exhibit with this title filed with the
         Company's Form 10-K for its fiscal year ended September 30, 1990.

(3)      Incorporated by reference to exhibit with this title filed with the
         Company's Registration Statement (#33-41207-LA) declared effective
         August 8, 1991.

(4)      Incorporated by reference to exhibit with this title filed with the
         Company's Form 10-K for its fiscal year ended December 31, 1991.

(5)      Incorporated by reference to exhibit with this title filed with the
         Company's Post Effective Amendment to its Registration Statement
         (#33-41207-LA) declared effective November 6, 1992.

(6)      Management contract or compensatory plan or arrangement required to be
         filed as an exhibit pursuant to applicable rules of the Securities and
         Exchange Commission.

(7)      Incorporated by reference to exhibit with this title filed with the
         Company's Form 10-K for its fiscal year ended December 31, 1995.

(8)      Incorporated by reference to exhibit with this title filed with the
         Company's Report on Form 8-K dated July 22, 1996.

(9)      Incorporated by reference to exhibit with this title filed with the
         Company's Registration Statement (#333-16547) declared effective
         November 20, 1996.

(10)     Incorporated by reference to exhibit with this title filed with the
         Company's Form 10-K for its fiscal year ended December 31, 1996.

(11)     Incorporated by reference to exhibit with this title filed with the
         Company's Report on Form 8-K dated April 14, 1997.

(12)     Incorporated by reference to exhibit with this title filed with the
         Company's Report on Form 8-K dated February 9, 1999.

(13)     Incorporated by reference to exhibit with this title filed with the
         Company's Form 10-K for its fiscal year ended December 31, 1997.

---------------
*        Compensation plan, contract or arrangement required to be filed as an
         exhibit pursuant to applicable rules of the Securities and Exchange
         Commission.


                                       11
<PAGE>   12

                                   SIGNATURES


Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this Report to be signed on its behalf
by the undersigned thereunto duly authorized.


                                             I-FLOW CORPORATION
                                             ------------------
                                                (Registrant)


Date:       May 12, 2000                     /s/ Donald M. Earhart
       -----------------------------         -----------------------------------
                                             Donald M. Earhart,
                                             Chairman, President and CEO



Date:       May 12, 2000                     /s/ Gayle L. Arnold
       -----------------------------         -----------------------------------
                                             Gayle L. Arnold,
                                             Chief Financial Officer


                                       12
<PAGE>   13

                                INDEX TO EXHIBITS

     Set forth below is a list of the exhibits included or incorporated by
reference as part of this report:

<TABLE>
<CAPTION>
     Exhibit No.                        Description
     -----------                        -----------
<C>                 <S>
           3.1      Restated Articles of Incorporation of the Company (2)

           3.2      Certificate of Amendment to Restated Articles of
                    Incorporation dated June 14, 1991 (3)

           3.3      Certificate of Amendment to Restated Articles of
                    Incorporation dated May 12, 1992 (4)

           3.4      Certificate of Determination covering Company's Series B
                    Preferred Stock filed with the Secretary of State on October
                    5, 1992 (4)

           3.5      Restated Bylaws as of July 22, 1991 of the Company (3)

           4.1      Specimen Common Stock Certificate (4)

           4.2      Warrant Agreement between the Company and American Stock
                    Transfer & Trust Company, as Warrant Agent, dated February
                    13, 1990 (1)

           4.3      Form of Warrant dated July 22, 1996, issued in conjunction
                    with the acquisition of Block Medical, Inc. (5)

          10.1      Employment Agreement with Donald M. Earhart dated May 16,
                    1990 (2)(6) *

          10.2      1987-1988 Incentive Stock Option Plan and Non-Statutory
                    Stock Option Plan Restated as of March 23, 1992 (5)(6) *

          10.3      1992 Non-Employee Director Stock Option Plan (4)(6)

          10.4      License and Transfer Agreement with SoloPak Pharmaceuticals
                    Inc., dated March 6, 1996 (7)

          10.5      1996 Stock Incentive Plan (6)(9) *

          10.6      Agreement for Purchase and Sale of Assets dated as of July
                    3, 1996 by and among I-Flow Corporation, Block Medical, Inc.
                    and Hillenbrand Industries, Inc. (8)
</TABLE>
<PAGE>   14

<TABLE>
<CAPTION>
     Exhibit No.                        Description
     -----------                        -----------
<C>                 <S>
          10.7      Employment Agreement with James J. Dal Porto dated September
                    6, 1996 (10) *

          10.8      Lease Agreement Between Industrial Developments
                    International, Inc. as Landlord and I-Flow Corporation as
                    Tenant dated April 14, 1997 (11)

          10.9      Agreement and Plan of Merger by and among I-Flow
                    Corporation, I-Flow Subsidiary, Inc., Venture Medical, Inc.,
                    and InfuSystems II, Inc. and the Shareholders of Venture
                    Medical, Inc. and InfuSystems II, Inc. (12)

          10.10     Loan and Security Agreement between Silicon Valley Bank and
                    I-Flow Corporation dated September 28, 1995 (13)

          10.11     Amendment to Loan Agreement between Silicon Valley Bank and
                    I-Flow Corporation dated March 2, 1999 (13)

          10.12     Agreement and Plan of Merger By and Among I-Flow
                    Corporation, Spinal Acquisition Corp., Spinal Specialties,
                    Inc. and the Shareholders of Spinal Specialties, Inc. dated
                    January 13, 2000

          27        Financial Data Schedule
</TABLE>

(1)      Incorporated by reference to exhibit with this title filed with the
         Company's Registration Statement (#33-32263-LA) declared effective
         February 1, 1990.

(2)      Incorporated by reference to exhibit with this title filed with the
         Company's Form 10-K for its fiscal year ended September 30, 1990.

(3)      Incorporated by reference to exhibit with this title filed with the
         Company's Registration Statement (#33-41207-LA) declared effective
         August 8, 1991.

(4)      Incorporated by reference to exhibit with this title filed with the
         Company's Form 10-K for its fiscal year ended December 31, 1991.

(5)      Incorporated by reference to exhibit with this title filed with the
         Company's Post Effective Amendment to its Registration Statement
         (#33-41207-LA) declared effective November 6, 1992.

(6)      Management contract or compensatory plan or arrangement required to be
         filed as an exhibit pursuant to applicable rules of the Securities and
         Exchange Commission.

(7)      Incorporated by reference to exhibit with this title filed with the
         Company's Form 10-K for its fiscal year ended December 31, 1995.

(8)      Incorporated by reference to exhibit with this title filed with the
         Company's Report on Form 8-K dated July 22, 1996.

(9)      Incorporated by reference to exhibit with this title filed with the
         Company's Registration Statement (#333-16547) declared effective
         November 20, 1996.

(10)     Incorporated by reference to exhibit with this title filed with the
         Company's Form 10-K for its fiscal year ended December 31, 1996.

(11)     Incorporated by reference to exhibit with this title filed with the
         Company's Report on Form 8-K dated April 14, 1997.

(12)     Incorporated by reference to exhibit with this title filed with the
         Company's Report on Form 8-K dated February 9, 1999.

(13)     Incorporated by reference to exhibit with this title filed with the
         Company's Form 10-K for its fiscal year ended December 31, 1997.

---------------
*        Compensation plan, contract or arrangement required to be filed as an
         exhibit pursuant to applicable rules of the Securities and Exchange
         Commission.