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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
 
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                                 SCHEDULE 14D-1
 
              TENDER OFFER STATEMENT PURSUANT TO SECTION 14(D)(1)
                     OF THE SECURITIES EXCHANGE ACT OF 1934
 
                               (AMENDMENT NO. 1)
 
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                              MCKESSON CORPORATION
                           (NAME OF SUBJECT COMPANY)
 
                          ECO ACQUISITION CORPORATION
                          A WHOLLY OWNED SUBSIDIARY OF
                             ELI LILLY AND COMPANY
                                   (BIDDERS)
 
COMMON STOCK, $2.00 PAR VALUE PER SHARE               581556 10 7
   (INCLUDING THE ASSOCIATED RIGHTS)     (CUSIP NUMBER OF CLASS OF SECURITIES)
     (TITLE OF CLASS OF SECURITIES)
 
                                J.B. KING, ESQ.
                       VICE PRESIDENT AND GENERAL COUNSEL
                             ELI LILLY AND COMPANY
                             LILLY CORPORATE CENTER
                          INDIANAPOLIS, INDIANA 46285
                                 (317) 276-2000
         (NAMES, ADDRESSES AND TELEPHONE NUMBERS OF PERSONS AUTHORIZED
           TO RECEIVE NOTICES AND COMMUNICATIONS ON BEHALF OF BIDDER)
 
                                WITH A COPY TO:
 
                             BERNARD E. KURY, ESQ.
                                DEWEY BALLANTINE
                          1301 AVENUE OF THE AMERICAS
                            NEW YORK, NEW YORK 10019
                                 (212) 259-7400
 
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  This Amendment No. 1 to the Schedule 14D-1 relates to a tender offer by ECO
Acquisition Corporation, a Delaware corporation and a wholly owned subsidiary
of Eli Lilly and Company, an Indiana corporation ("Parent"), to purchase all
outstanding shares of common stock, par value $2.00 per share and the
associated Rights (as defined in the Offer to Purchase) (collectively, the
"Shares"), of McKesson Corporation, a Delaware corporation, at a purchase price
of $76.00 per Share, net to the seller in cash, without interest, upon the
terms and subject to the conditions set forth in the Offer to Purchase, dated
July 15, 1994 (the "Offer to Purchase"), and the related Letter of Transmittal
(which together constitute the "Offer"), copies of which were attached as
Exhibits (a)(1) and (a)(2), respectively, to the Schedule 14D-1 filed with the
Securities and Exchange Commission on July 15, 1994 (the "Schedule 14D-1"). The
purpose of this Amendment No. 1 is to amend and supplement Items 10 and 11 of
the Schedule 14D-1 as described below.
 
ITEM 10. ADDITIONAL INFORMATION TO BE FURNISHED.
 
  The response to Item 10 is hereby amended and supplemented as follows:
 
  On July 26, 1994, Parent received a request for additional information from
the Federal Trade Commission. The request extends the waiting period until
11:59 p.m., New York City time, on the tenth calendar day after the date of
substantial compliance with the request unless the Federal Trade Commission
decides to terminate the waiting period earlier. The expiration of such waiting
period is a condition to the Offer, and accordingly, the Offer may not be
consummated until its expiration. Parent intends to use its best efforts to
comply with this request as expeditiously as practicable.
 
ITEM 11. MATERIAL TO BE FILED AS EXHIBITS.
 
  (a)(17)   --Form of press release issued by Parent on July 27, 1994.
 
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                                   SIGNATURE
 
  AFTER DUE INQUIRY AND TO THE BEST OF ITS KNOWLEDGE AND BELIEF, EACH OF THE
UNDERSIGNED CERTIFIES THAT THE INFORMATION SET FORTH IN THIS STATEMENT IS TRUE,
COMPLETE AND CORRECT.
 
                                          Eli Lilly and Company
 
                                              
                                          By:     /s/ James M. Cornelius
                                              ---------------------------------
                                              Name:  James M. Cornelius
                                              Title: Vice President, Finance and
                                                     Chief Financial Officer
 
                                          ECO Acquisition Corporation
 
                                              
                                          By:    /s/ Charles E. Schalliol
                                              ---------------------------------
                                              Name:  Charles E. Schalliol
                                              Title: President
 
Dated: July 27, 1994
 
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                                                                 EXHIBIT (A)(17)
 
             LILLY AND MCKESSON RECEIVE SECOND REQUEST FROM FTC FOR
                         INFORMATION ON PCS TRANSACTION
 
July 27, 1994--Eli Lilly and Company and McKesson Corp. today announced that
they have received requests from the Federal Trade Commission (FTC) for
additional information under the provisions of the Hart-Scott-Rodino Antitrust
Improvements Act in connection with the previously-announced acquisition of
McKesson's PCS Health Systems business by Lilly in a corporate restructuring.
 
Lilly and McKesson said they will promptly provide the requested information.
The FTC request will extend the Hart-Scott-Rodino waiting period until ten days
after the date on which Lilly substantially complies with the FTC's request,
unless the FTC decides to terminate the waiting period earlier.
 
Lilly and McKesson said such requests are not unusual for an acquisition of
this size. The companies also stated that they believe that the proposed
transaction fully complies with federal antitrust laws and they continue to
expect to close the transaction in late September or early October 1994.
 
As announced on July 11, Lilly has commenced a cash tender offer for all
outstanding shares of McKesson's common stock at a price of $76 per share. In
addition, prior to the consummation of the tender offer, McKesson will transfer
all its non-PCS assets and liabilities to a newly-formed corporation and will
distribute the common stock of the new McKesson to the stockholders of
McKesson.
 
Lilly is a global research-based pharmaceutical corporation headquartered in
Indianapolis, Indiana, that is working with its customers worldwide to help
ensure that diseases are prevented, managed, and cured with maximum benefit and
minimum cost to patients and society.
 
McKesson, headquartered in San Francisco, is the world's largest distributor of
pharmaceuticals and related health care products, with operations in the U.S.,
Canada, and Mexico.
 
Contact: Edward A. West-Lilly
         (317) 276-3655
         Marvin Krasnansky-McKesson
         (415) 983-8316