EXHIBIT 24 POWER OF ATTORNEY KNOW ALL MEN BY THESE PRESENTS, that each of the undersigned officers and/or directors of Schering-Plough Corporation, a New Jersey corporation (herein called the "Corporation"), does hereby constitute and appoint William J. Silbey, Thomas H. Kelly and Edward Smith, or any of them, his or her true and lawful attorney or attorneys and agent or agents, to do any and all acts and things and to execute any and all instruments which said attorney or attorneys and agent or agents may deem necessary or advisable to enable the Corporation to comply with the Securities Exchange Act of 1934, as amended, and any rules, regulations, requirements or requests of the Securities and Exchange Commission thereunder or in respect thereof in connection with the filing under said Act of the Annual Report of the Corporation on Form 10-K for the fiscal year ended December 31, 1999 (herein called the "Form 10-K"); including specifically, but without limiting the generality of the foregoing, the power and authority to sign the respective names of the undersigned officers and/or directors as indicated below to the Form 10-K and/or to any amendment of the Form 10-K and each of the undersigned does hereby ratify and confirm all that said attorney or attorneys and agent or agents, or any of them, shall do or cause to be done by virtue hereof. IN WITNESS WHEREOF, each of the undersigned has subscribed these presents this 22nd day of February, 2000. /s/ Richard Jay Kogan /s/ Jack L. Wyszomierski Richard Jay Kogan, Chairman and Jack L. Wyszomierski, Executive Chief Executive Officer; Director Vice President and Chief Financial Officer /s/ Thomas H. Kelly /s/ H. Barclay Morley Thomas H. Kelly, Vice President H. Barclay Morley and Controller; Principal Director Accounting Officer /s/ Hans W. Becherer /s/ Carl E. Mundy, Jr. Hans W. Becherer Carl E. Mundy, Jr. Director Director /s/ Raul E. Cesan /s/ Richard de J. Osborne Raul E. Cesan Richard de J. Osborne Director Director /s/ Hugh A. D'Andrade /s/ Patricia F. Russo Hugh A. D'Andrade Patricia F. Russo Director Director /s/ David C. Garfield /s/ William A. Schreyer David C. Garfield William A. Schreyer Director Director /s/ Regina E. Herzlinger /s/ Robert F. W. van Oordt Regina E. Herzlinger Robert F. W. van Oordt Director Director /s/ Robert P. Luciano /s/ Arthur F. Weinbach Robert P. Luciano Arthur F. Weinbach Director Director /s/ Donald L. Miller /s/ James Wood Donald L. Miller James Wood Director Director