Exhibit 23.1 CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS As independent public accountants, we hereby consent to the incorporation by reference in this registration statement of: (i) our supplemental report dated January 14, 1999, included in the Abbott Laboratories Annual Report on Form 10-K for the year ended December 31, 1998 and (ii) our report dated January 14, 1999, incorporated by reference in the Abbott Laboratories Annual Report on Form 10-K for the year ended December 31, 1998 and to all references to our firm in the registration statement. /s/ Arthur Andersen LLP ----------------------- ARTHUR ANDERSEN LLP Chicago, Illinois December 17, 1999