1 EXHIBIT 23(a) INDEPENDENT AUDITORS' CONSENT We consent to the incorporation by reference in this Registration Statement of Cardinal Health, Inc. on Form S-8 of our report dated August 10, 1999, appearing in the Annual Report on Form 10-K of Cardinal Health, Inc. for the year ended June 30, 1999. /s/ Deloitte & Touche LLP DELOITTE & TOUCHE LLP Columbus, Ohio November 4, 1999 15