[Code of Federal Regulations] [Title 21, Volume 6] [Revised as of April 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 21CFR524.660] [Page 297] TITLE 21--FOOD AND DRUGS CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PART 524_OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS--Table of Contents Sec. 524.660 Dimethyl sulfoxide ophthalmic and topical dosage forms.