Sir,- My wife, a dental practitioner has drawn my attention to this article, (BDJ 2003, 195: 495) which I find extremely comprehensive. My interest is that, as a retired consultant accident and emergency surgeon (or ER physician in the US) I have bouts of supraventricular tachycardia or atrial fibrillation following quadrupal coronary artery bypass grafting nine years ago. I had the unfortunate experience of being allergic to warfarin following my first coronary thrombosis, so I have to use a very obscure coumarin derivative, phenindione (phenyl-indane-dione).

I do not know if this is licensed by the Food and Drug Administration (FDA), but it keeps me free of thrombotic episodes, and apparently works in the same way as warfarin, enough to continue in medical activities in a less stressful field. It might be an idea to include this drug in any further survey.

One of the authors of the paper P.B. Lockhart replies: I would like to thank Dr Flowers for his addition to our paper. I looked up phenindione (dindevan) in our drug text and did not find it. This does not mean that it is not an FDA approved drug under another name and in limited use in the US, but our cardiologist did not recognize it and he should know. I looked it up in the British National Formulary and it appears to have the same precautions as warfarin and therefore I suspect it should be thought of in the same way from the standpoint of bleeding from invasive dental procedures.