Rapid responses from bmj.com: Metformin and measuring renal function

doi:10.1136/bmjusa.03030004

BMJ 2003;327:E203 (4 October), doi:10.1136/bmjusa.03030004 (published 12 April 2003)

BMJ USA: Letter

Rapid responses from bmj.com

Metformin and measuring renal function

Following is an edited excerpt from one of the Rapid Responsesgenerated by this article, which can be read in their entiretyat http://bmj.com/cgi/eletters/326/7379/4—Editor

From BMJ USA 2003;Mar:132

Jones and colleagues provide compelling arguments for a review of the contraindications to metformin use. However, it isdifficult to understand the rationale behind their advocacyof serum creatinine concentration in determining the appropriatenessof metformin. Creatinine clearance is a much better objectiveassessment of renal function, and it reduces the arbitrarynature of the cutoff point for renal failure described byJones et al. It also allows some guidance for metformin usein elderly patients, some of whom may have significant renalimpairment but a serum creatinine concentration within thenormal range. Recent Australian guidelines on the use of oralhypoglycemic agents employ creatinine clearance as a measureof renal function in determining an appropriate dose of metformin.These guidelines present a practical alternative to the viewof Jones et al that the term "renal impairment" is vague andunhelpful.