EXHIBIT 24


                               POWER OF ATTORNEY


     KNOW ALL MEN BY THESE PRESENTS THAT the undersigned directors and officers
of McKesson HBOC, Inc., a Delaware corporation (the "Company") do hereby
constitute and appoint Ivan D. Meyerson and Kristina Veaco his or her true and
lawful attorney and agent, each with full power and authority (acting alone and
without the other) to execute in the name and on behalf of the undersigned as
such Director and/or Officer, a Registration Statement on Form S-8 under the
Securities Act of 1933, as amended, with respect to the registration of shares
of the Company's Common Stock, par value $.01 per share, that may be issued by
the Company in connection with certain stock options and to execute any and all
amendments to such Registration Statement, whether filed prior or subsequent to
the time such Registration Statement becomes effective.  The undersigned hereby
grants unto such attorneys and agents, and each of them, full power of
substitution and revocation in the premises and hereby ratifies and confirms all
that such attorneys and agents may do or cause to be done by virtue of these
presents.

/s/ Alfred C. Eckert III                    /s/ James V. Napier
Director                                    Director

/s/ Tully M. Friedman                       /s/ David S. Pottruck
Director                                    Director

/s/ John H. Hammergren,                     /s/ Carl E. Reichardt
Co-President and                            Director
Co-Chief Executive Officer and Director
(co-Principal Executive Officer)

/s/ Alton F. Irby III                       /s/ Alan Seelenfreund
Director                                    Chairman of the Board and Director


/s/ M. Christine Jacobs                     /s/ Jane E. Shaw
Director                                    Director

/s/ David L. Mahoney                        /s/ Heidi E. Yodowitz,
Co-Presdient and                            Vice President, Controller and
Co-Chief Executive Officer and Director     Acting Chief Financial Officer
(Co-Principal Executive Officer)

/s/ Gerald E. Mayo
Director



Dated: January 20, 2000