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                         [OMNICARE NEWS RELEASE LETTERHEAD]

[GRAPHIC]                                               FOR IMMEDIATE RELEASE


                 OMNICARE ANNOUNCES DEFINITIVE AGREEMENT TO ACQUIRE
                            AMERICAN MEDSERVE CORPORATION


        CINCINNATI, OHIO, AND NAPERVILLE, ILLINOIS, AUGUST 8, 1997 . . .
Omnicare, Inc. (NYSE:OCR) and American Medserve Corporation (NASDAQ:AMCI) today
announced the execution of a definitive merger agreement pursuant to which
Omnicare will acquire for cash all of the outstanding shares of American
Medserve Corporation.

        Under terms of the agreement, a wholly owned subsidiary of Omnicare
will commence a cash tender offer of $18.00 per share for all of the
outstanding shares of American Medserve Corporation, representing a purchase
price of approximately $222.6 million. Additionally, Omnicare will assume
American Medserve Corporation's liabilities, including long-term debt of
approximately $11.6 million. The acquisition will be accounted for as a
purchase transaction. Given the economics of scale and cost synergies
anticipated from the merger, the acquisition of American Medserve Corporation
is expected to be non-dilutive to Omnicare's earnings per share in 1997 and
accretive in 1998.

        American Medserve Corporation, based in Naperville, Illinois, provides
comprehensive pharmacy and related services to approximately 51,400 residents
in 720 long-term care facilities in 11 states. Additionally, American Medserve
Corporation is a joint venture partner with an affiliate of The Evangelical
Lutheran Good Samaritan Society, which ranks as the nation's fifth-largest
nursing home operator, serving 27,000 residents. Based on revenues reported for
the quarter ended March 31, 1997, American Medserve Corporation's annualized
revenues are approximately $144.0 million.

        The transaction, which has been approved by the boards of


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directors of both Omnicare and American Medserve Corporation, is subject to the
tender of at least a majority of the outstanding shares of American Medserve
Corporation on a fully diluted basis, customary regulatory approval and the
satisfaction of certain other conditions. The tender offer will commence within
five business days and will remain open for 20 business days, unless extended.
Following the consummation of the tender offer, Omnicare will acquire any of the
remaining outstanding shares of American Medserve Corporation in a cash merger
transaction valued at $18.00 per share.

        With the completion of this acquisition, Omnicare will provide pharmacy
and related consulting services to approximately 413,000 residents in over
5,100 long-term care facilities in 35 states. Based on revenues for the quarter
ended June 30, 1997, Omnicare's annualized revenues, following the transaction,
will be in excess of $950.0 million.

        "We believe the combination of Omnicare and American Medserve
Corporation, two companies recognized as leading consolidators in the
institutional pharmacy industry, will create a dynamic organization with the
resources, clinical programs and pharmacy management experience necessary to
capitalize on the major growth opportunities in geriatric pharmaceutical care,"
said Joel F. Gemunder, Omnicare president.

        "The addition of American Medserve Corporation will significantly
expand Omnicare's core business of providing high-quality pharmaceutical care
to the nation's elderly and will create economies of scale that allow both of
our organizations to operate more efficiently," he said.

        The acquisition of American Medserve Corporation will mark Omnicare's
entry into six new states and will broaden Omnicare's network of existing
pharmacies in five other states, including Illinois, Pennsylvania and New York,
which rank among the nation's largest in terms of nursing home population.

        "American Medserve Corporation has built a well-managed group of
entrepreneurial pharmacy operations and has developed important strategic
alliances, including its partnership with The Evangelical Lutheran Good
Samaritan Society. We look forward to the opportunity to bring our broad array
of clinical programs,

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including the Omnicare Geriatric Pharmaceutical Care Guidelines(R), to American
Medserve Corporation's pharmacy operations and their client nursing facilities.
Together, we can provide the basis for outstanding geriatric pharmaceutical  are
in the most cost-effective manner," Mr. Gemunder concluded.

     "American Medserve Corporation and Omnicare have become strong, successful
long-term care providers by meeting the increasingly complex needs of their
client facilities with innovative services, and this transaction will provide
both organizations with the resources to expand those programs even further,"
said Timothy L. Burfield, American Medserve Corporation president and chief
executive officer.

     "We also believe this agreement provides our shareholders with an
attractive value for their investment in our company," Mr. Burfield said.


     Omnicare is a leading independent provider of professional pharmacy and
related consulting services for long-term care facilities such as nursing homes,
retirement centers and other institutional health care facilities. Omnicare
currently provides pharmacy and related consulting services to approximately
361,400 residents in over 4,400 long-term care facilities.

     (Statements in this press release concerning Omnicare's and American
Medserve Corporation's business outlook or future economic performances,
anticipated profitability, revenues, expenses or other financial items,
anticipated cost synergies, economies of scale and product or service line
growth, together with other statements that are not historical facts, are
forward-looking statements that are estimates reflecting the best judgment of
Omnicare and American Medserve Corporation based on currently available
information. Such forward-looking statements involve risks, uncertainties and
other factors that could cause results to differ materially from those stated.
These include trends for the continued growth of the pharmacy businesses of
Omnicare and American Medserve Corporation, the realization of anticipated
revenues, profitability and cost synergies of the combined companies, and other
risks and uncertainties described in Omnicare's and American Medserve
Corporation's reports and filings with the Securities and Exchange Commission.
There can 

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be no assurance that such factors will not affect the accuracy of such
forward-looking statements, and neither Omnicare nor American Medserve
Corporation assumes any obligation to update the information in this release.)

        For more information on Omnicare, Inc. via the Internet, including a
full menu of news releases, visit our Corporate News on The Net site at
http://www.businesswire.com/cnn/ocr.htm

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OMNICARE CONTACTS:                        AMERICAN MEDSERVE CORPORATION:
Cheryl D. Hodges                          Charles R. Wallace
(513) 762-6967                            (630) 717-2904
     or
Gary L. Rhodes
(513) 762-6660





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