Recently a new oral anti-diabetic drug, metformin, was introduced in the United States for treatment of noninsulin-dependent diabetes (NIDDM) in humans. Metformin offers promise as an effective oral anti-diabetic drug in cats. An appropriate dose needs to be determined before metformin can be tested in diabetic cats. The purpose of this pilot study is to determine the pharmacokinetics properties (action, duration and breakdown) of metformin following single dose oral administration to healthy cats. Results of this study should allow determination of an appropriate dose for cats – information that will then lead to additional studies to determine side effects and effectiveness of the drug to treat NIDDM in cats.