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                                                                    Exhibit 31.1

                                CERTIFICATION OF
                             CHIEF EXECUTIVE OFFICER


I, Barry R. Edwards, certify that:

1.         I have reviewed this quarterly report on Form 10-Q for the three
           months ended September 30, 2004 of Impax Laboratories, Inc.

2.         Based on my knowledge, this quarterly report does not contain any
           untrue statement of a material fact, or omit to state a material fact
           necessary to make the statements made, in light of the circumstances
           under which such statements were made, not misleading with respect to
           the period covered by this report.

3.         Based on my knowledge, the financial statements, and other financial
           information included in this quarterly report, fairly present in all
           material respects, the financial condition, results of operations and
           cash flows of the registrant as of, and for, the periods presented in
           this report.

4.         The registrant's other certifying officer(s) and I are responsible
           for establishing and maintaining disclosure controls and procedures
           (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
           registrant and have:

                  a)  Designed such disclosure controls and procedures, or
                      caused such disclosure controls and procedures to be
                      designed under our supervision, to ensure that material
                      information relating to the registrant, including its
                      consolidated subsidiaries, is made known to us by others
                      within those entities, particularly during the period in
                      which this quarterly report is being prepared;

                  b)  Evaluated the effectiveness of the registrant's disclosure
                      controls and procedures and presented in this report our
                      conclusions about the effectiveness of the disclosure
                      controls and procedures, as of the end of the period
                      covered by this report based on such evaluation; and

                  c)  Disclosed in this report any change in the registrant's
                      internal control over financial reporting that occurred
                      during the registrant's most recent fiscal quarter (the
                      registrant's fourth fiscal quarter in the case of an
                      annual report) that has materially affected, or is
                      reasonably likely to materially affect, the registrant's
                      internal control over financial reporting, and

5.         The registrant's other certifying officer(s) and I have disclosed,
           based on our most recent evaluation of internal control over
           financial reporting, to the registrant's auditors and the audit
           committee of registrant's board of directors (or persons performing
           the equivalent functions):

                  a)  All significant deficiencies and material weaknesses in
                      the design or operation of internal control over financial
                      reporting which are reasonably likely to adversely affect
                      the registrant's ability to record, process, summarize and
                      report financial information; and

                  b)  Any fraud, whether or not material, that involves
                      management or other employees who have a significant role
                      in the registrant's internal control over financial
                      reporting.




                                                     /s/  Barry R. Edwards
                                                     --------------------------
                                                          Barry R. Edwards
                                                       Chief Executive Officer


                                                     --------------------------
                                                          November 15, 2004