SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                           --------------------------

                                SCHEDULE 14D-1/A

                           --------------------------

                   TENDER OFFER STATEMENT PURSUANT TO SECTION
                14(D)(1) OF THE SECURITIES EXCHANGE ACT OF 1934

                            -------------------------

                                 MEDISENSE, INC.

                            (NAME OF SUBJECT COMPANY)
                            -------------------------

                             AAC ACQUISITION, INC.,
                          a wholly owned subsidiary of
                               ABBOTT LABORATORIES

                                    (BIDDERS)
                            -------------------------

                                Common Stock and
                              Class B Common Stock

                         (TITLE OF CLASS OF SECURITIES)

                            -------------------------

                                    584960108

                      (CUSIP NUMBER OF CLASS OF SECURITIES)

                            -------------------------

                                 Jose M. de Lasa
                        Senior Vice President, Secretary
                               and General Counsel
                               Abbott Laboratories
                              100 Abbott Park Road
                        Abbott Park, Illinois  60064-3500
                                 (847) 937-6100

                  (NAME, ADDRESS AND TELEPHONE NUMBER OF PERSON
              AUTHORIZED TO RECEIVE NOTICES AND COMMUNICATIONS ON
                                BEHALF OF BIDDER)

                                    Copy to:
                                Robert A. Helman
                              Mayer, Brown & Platt
                            190 South LaSalle Street
                               Chicago, IL  60603
                                 (312) 782-0600

                                Page 1 of 6 Pages
                       Exhibit Index is located on Page 6



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CUSIP No.:  584960108                 14D-1            Page 2 of 6 Pages
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1.   Name of Reporting Person:  AAC Acquisition, Inc.
     SS or IRS Identification No. of Above Person:  None.
     Name of Reporting Person:  Abbott Laboratories
     SS or IRS Identification No. of Above Person: 36-0698440

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2.   Check the Appropriate Box if a Member of a Group:                (a)   / /
                                                                      (b)   / /

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3.   SEC Use Only:

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4.   Sources of Funds:  WC

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5.   Check if Disclosure of Legal Proceedings is Required Pursuant to Items 2(e)
     or 2(f):                                                               / /

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6.   Citizenship or Place of Organization:  Massachusetts (AAC Acquisition,
     Inc.); Illinois (Abbott Laboratories)

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7.   Aggregate Amount Beneficially Owned by Each Reporting Person:
     19,121,138 Shares

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8.   Check if the Aggregate in Row (7) Excludes Certain Shares:             / /

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9.   Percent of Class Represented by Amount in Row (7):  94.70%

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10.  Type of Reporting Person:  CO (AAC Acquisition, Inc.)
                                 CO (Abbott Laboratories)

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     This Amendment No. 2 amends and supplements the Tender Offer Statement on
Schedule 14D-1 dated April 4, 1996, as amended (the "Schedule 14D-1") of Abbott
Laboratories, an Illinois corporation ("Parent"), and AAC Acquisition, Inc., a
Massachusetts corporation and wholly-owned subsidiary of Parent (the
"Purchaser"), filed in connection with the Purchaser's offer to purchase any and
all shares of the common stock, $.01 par value per share (the "Common Stock")
and Class B common stock, $.01 par value per share (the "Class B Common Stock"
and together with the Common Stock, the "Shares") of MediSense, Inc., a
Massachusetts corporation (the "Company"), upon the terms and subject to the
conditions set forth in the Schedule 14D-1 (the "Offer").  Capitalized terms
used but not otherwise defined herein shall have the meanings assigned to those
terms in the Schedule 14D-1.

ITEM 5.   PURPOSE OF THE TENDER OFFER AND PLANS OR PROPOSALS OF THE BIDDER.

     Pursuant to the terms of the Merger Agreement, it is expected that as soon
as practicable following the expiration of the Offer certain directors of the
Company will resign as directors and Gary P. Coughlan, Miles D. White and Jose
M. de Lasa, designees of Parent, will be elected as directors of the Company.

     As soon as practicable following the expiration of the Offer, the Company
will call a special meeting of its shareholders for the purpose of adopting the
Merger Agreement.  Purchaser intends to vote all Shares held by it in favor of
adoption of the Merger Agreement and, therefore, adoption of the Merger
Agreement by the Company's shareholders is assured.

ITEM 6.   INTEREST IN SECURITIES OF THE SUBJECT COMPANY.

     The Offer expired at 12:00 midnight, New York City time, on Wednesday, May
1, 1996.  On May 2, 1996, Purchaser accepted for payment and, therefore,
purchased all of the 19,121,138 Shares which were validly tendered and not
withdrawn as of the expiration of the Offer, including 2,217,972 Shares
which were tendered pursuant to guaranteed delivery procedures, at the Offer
price of $45.00 per Share. As a result, Purchaser and Parent beneficially own 
94.70% of the outstanding Shares of the Company on a fully diluted basis.

ITEM 7.   CONTRACTS, ARRANGEMENTS, UNDERSTANDINGS OR RELATIONSHIPS WITH RESPECT
          TO THE SUBJECT COMPANY'S SECURITIES.

     By executing the Letter of Transmittal, each tendering stockholder has
appointed designees of Purchaser as such stockholders' proxies with respect to
the tendered Shares.  All such proxies became effective as of Purchaser's
acceptance for payment of the Shares tendered in response to the Offer.  Such

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proxies are irrevocable and coupled with an interest in the tendered Shares.

ITEM 10.  ADDITIONAL INFORMATION.

     On May 2, 1996, Parent issued the press release attached hereto as Exhibit
(a)(11).  The full text of the press release is incorporated herein by
reference.

ITEM 11.  MATERIAL TO BE FILED AS EXHIBITS

     (a)(11)   Press Release dated May 2, 1996.

                                        4



                                    SIGNATURE

     After due inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.



Dated:  May 2, 1996


                                        AAC ACQUISITION, INC.


                                        /s/Gary P. Coughlan
                                        ------------------------------------
                                        Name:  Gary P. Coughlan
                                        Title:  Vice President and Treasurer


                                        ABBOTT LABORATORIES


                                        /s/Gary P. Coughlan
                                        ------------------------------------
                                        Name:  Gary P. Coughlan
                                        Title:  Senior Vice President, Finance
                                                 and Chief Financial Officer

                                        5



                                  EXHIBIT INDEX



Exhibit                           Description
- -------                           -----------


(a)(11)                           Press Release dated May 2, 1996.



                                                                 Exhibit (a)(11)

                                                       FOR IMMEDIATE RELEASE

                                                       Media:
                                                       Rick Moser
                                                       Abbott Laboratories
                                                       (847) 937-8943

                                                       Financial Community:
                                                       Patricia Bergeron
                                                       Abbott Laboratories
                                                       (847) 938-5633

ABBOTT LABORATORIES ACQUIRES CONTROL OF MEDISENSE, INC.

     ABBOTT PARK, Ill., May 2, 1996 -- Abbott Laboratories announced today that
it has acquired control of MediSense, Inc. Abbott's cash tender offer to
purchase all of the outstanding common stock of MediSense, Inc. expired as
schedules at midnight, Eastern Standard Time, on Wednesday, May 1, 1996.  The
tender offer has not been extended.

     A total of 19,121,138 shares of MediSense common stock were validly
tendered and not withdrawn prior to the expiration of the offer, including
2,217,972 shares subject to guaranteed delivery procedures.  Abbott has accepted
all of these shares for payment.  These shares represent approximately 94
percent of MediSense's outstanding shares on a fully diluted basis.

     "Our acquisition of MediSense gives us a prominent position in an
attractive new business for Abbott and will create many opportunities for
synergy with other Abbott divisions," said Duane L. Burnham, Abbott chairman and
chief executive officer.  "We are proud to join MediSense's superior technology
and outstanding people with our company."



     As the final step of the acquisition process, MediSense will be merged with
a wholly owned subsidiary of Abbott.  To complete this step, a special meeting
of MediSense shareholders will be called to approve the merger.  Given Abbott's
controlling interest int he company, shareholder approval is assured.

     Under the terms of Abbott's March 29, 1996, definitive agreement with
MediSense, Abbott will pay the MediSense equity holders approximately $876
million, net of the exercise price on existing MediSense options, for 100
percent of the equity in MediSense.

     MediSense is the biosensor technology leader in blood glucose self-testing
systems for people with diabetes.

     According to Miles D. White, senior vice president, diagnostics operations,
Abbott has other internal and external initiatives underway to secure industry-
leading technology in glucose monitoring.  "In addition to providing immediate
access to the fastest-growing segment of the worldwide diagnostics market,
MediSense's research and development program will augment Abbott's existing work
to develop and commercialize future non-invasive monitoring technologies," said
White.

     Abbott Laboratories is a worldwide manufacturer of health care products,
employing 50,000 people.  In 1995, the company's sales and net earnings were
$10.0 billion and $1.7 billion, respectively, with earnings per share of $2.12.

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