BRUCE L. DOWNEY
                          LIMITED POWER OF ATTORNEY FOR
                        SECTION 16 REPORTING OBLIGATIONS

        I hereby make, constitute and appoint each of Stephen T. Falk, John M.
Adams, Jr., Aneezal H. Mohamed and James E. Barnett, each acting individually,
as the undersigned's true and lawful attorney-in-fact, with full power and
authority as hereinafter described on behalf of and in the name, place and stead
of the undersigned to:

        (1)     prepare, execute, acknowledge, deliver and file Forms 3, 4, and
5 (including any amendments thereto) with respect to the securities of Cardinal
Health, Inc., an Ohio corporation (the "Company"), with the United States
Securities and Exchange Commission (the "SEC"), any national securities
exchanges and the Company, as considered necessary or advisable under Section
16(a) of the United States Securities Exchange Act of 1934 and the rules and
regulations promulgated thereunder, as amended from time to time (the "Exchange
Act");

        (2)     prepare and execute in the undersigned's name and on the
undersigned's behalf, and to submit to the SEC a Form ID, including amendments
thereto, and any other documents necessary or appropriate to obtain codes and
passwords enabling the undersigned to make electronic filings with the SEC of
reports required by Section 16(a) of the Exchange Act or any rule or regulation
of the SEC;

        (3)     prepare, execute, acknowledge, deliver and file Form 144s
(including any amendments or supplements thereto) with respect to the sale of
securities of the Company by the undersigned, with the SEC, any national
securities exchanges and the Company, as considered necessary or advisable under
Rule 144 of the Securities Act of 1933 and the rules and regulations promulgated
thereunder, as amended from time to time;

        (4)     seek or obtain, as the undersigned's representative and on the
undersigned's behalf, information on transactions in the Company's securities
from any third party, including brokers, employee benefit plan administrators
and trustees, and the undersigned hereby authorizes any such person to release
any such information to the attorney-in-fact and approves and ratifies any such
release of information; and

        (5)     perform any and all other acts which in the discretion of such
attorney-in-fact are necessary or desirable for and on behalf of the undersigned
in connection with the foregoing.

        The undersigned acknowledges that:

        (1) this Limited Power of Attorney authorizes, but does not require,
each such attorney-in-fact to act in his discretion on information provided to
such attorney-in-fact without independent verification of such information;

        (2) any documents prepared and/or executed by each such attorney-in-fact
on behalf of the undersigned pursuant to this Limited Power of Attorney will be
in such form and will contain such information and disclosure as such
attorney-in-fact, in his discretion, deems necessary or desirable;

        (3) neither the company nor such attorney-in-fact assumes (i) any
liability for the undersigned's responsibility to comply with the requirement of
the Exchange Act, (ii) any liability of the undersigned for any failure to
comply with such requirements, or (iii) any obligation or liability of the
undersigned for profit disgorgement under Section 16(b) of the Exchange Act; and

        (4) this Power of Attorney does not relieve the undersigned from
responsibility for compliance with the undersigned's obligations under the
Exchange Act, including without limitation, the reporting requirements under
Section 16 of the Exchange Act.

        The undersigned hereby gives and grants each of the foregoing
attorneys-in-fact full power and authority to do and perform all and every act
and thing whatsoever required, necessary or appropriate to be done in connection
with the undersigned and the undersigned also hereby ratifies all that each such
attorney-in-fact shall lawfully do or cause to be done by virtue of this Limited
Power of Attorney.

        This Power of Attorney shall remain in full force and effect until
revoked by the undersigned in a signed writing delivered to each such
attorney-in-fact.

        IN WITNESS WHEREOF, the undersigned has caused this Limited Power of
Attorney to be executed as of this 31st day of August, 2009.

                                        /s/ Bruce L. Downey
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                                        Signature

                                        BRUCE L. DOWNEY
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