Exhibit 99.1
IMPAX
LABORATORIES, INC.

COMPANY CONTACTS:                       INVESTOR RELATIONS CONTACTS:
IMPAX Laboratories, Inc.                Lippert/Heilshorn & Associates, Inc.
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Barry R. Edwards, CEO                   Kim Sutton Golodetz (kgolodetz@lhai.com)
(215) 933-0323 Ext. 4360                (212) 838-3777
Larry Hsu, Ph.D. President              Bruce Voss (bvoss@lhai.com)
(510) 476-2000 Ext. 1111                (310) 691-7100
Cornel C. Spiegler, CFO                 www.lhai.com
(215) 289-2220 Ext. 1706                ------------
www.impaxlabs.com
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                        IMPAX RECEIVES FINAL FDA APPROVAL
                         FOR GENERIC VERSION OF ZYBAN(R)

                          SEVENTH ANDA APPROVAL IN 2004



HAYWARD, CALIF. (MAY 27, 2004) - IMPAX LABORATORIES, INC. (NASDAQ NM: IPXL)
announced that the U.S. Food and Drug Administration (FDA) has granted final
marketing approval to the Company's Abbreviated New Drug Application (ANDA) for
its generic version of Zyban(R), Bupropion Hydrochloride 150 mg Controlled
Release Tablets. GlaxoSmithKline (NYSE: GSK) markets Zyban for smoking
cessation. According to NDCHealth, U.S. sales of Zyban were approximately $63
million in the twelve months ended March 31, 2004.

"We are pleased to have received this, our seventh ANDA approval this year,"
said Larry Hsu, Ph.D. IMPAX Laboratories, Inc. President.

IMPAX currently has 15 applications pending at the FDA, including five
tentatively approved, which address approximately $5.3 billion in U.S. product
sales for the twelve months ended March 31, 2004, based on NDCHealth data.
Twelve of these filings were made under Paragraph IV of the Hatch-Waxman
Amendments.

IMPAX Laboratories, Inc. is a technology based specialty pharmaceutical company
applying its formulation expertise and drug delivery technology to the
development of controlled-release and specialty generics in addition to the
development of branded products. IMPAX markets its generic products through its
Global Pharmaceuticals division and intends to market its branded products
through the IMPAX Pharmaceuticals division. Additionally, where strategically
appropriate, IMPAX has developed marketing partnerships to fully leverage its
technology platform. IMPAX Laboratories is headquartered in Hayward, California,
and has a full range of capabilities in its Hayward and Philadelphia facilities.
For more information, please visit the Company's Web site at: www.impaxlabs.com.

"Safe Harbor" statement under the Private Securities Litigation Reform Act of
1995:
To the extent any statements made in this news release contain information that
is not historical, these statements are forward-looking in nature and express
the beliefs and expectations of management. Such statements are based on current





expectations and involve a number of known and unknown risks and uncertainties
that could cause Impax's future results, performance or achievements to differ
significantly from the results, performance or achievements expressed or implied
by such forward-looking statements. Such risks and uncertainties include, but
are not limited to, Impax's ability to obtain sufficient capital to fund its
operations, the difficulty of predicting FDA filings and approvals, consumer
acceptance and demand for new pharmaceutical products, the impact of competitive
products and pricing, Impax's ability to successfully develop and commercialize
pharmaceutical products, Impax's reliance on key strategic alliances, the
uncertainty of patent litigation, the availability of raw materials, the
regulatory environment, dependence on patent and other protection for innovative
products, exposure to product liability claims, fluctuations in operating
results and other risks detailed from time to time in Impax's filings with the
Securities and Exchange Commission. Forward-looking statements speak only as to
the date on which they are made, and Impax undertakes no obligation to update
publicly or revise any forward-looking statement, regardless of whether new
information becomes available, future developments occur or otherwise.
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