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Hey everyone. I just got home from the nursing home where we are doing our clinicals, and I have a quick question. Reading through our pt's chart, I noticed that he is taking Coumadin. Our Instructor told us to research all the drugs our Pt's were on before we go back tomorrow. I was looking on drugs.com, and under Coumadin, it says do not drink cranberry juice, or eat cranberries. Does anyone know why this is? The only reason I am asking is because Cranberry juice is about the only thing my pt. drank today.
to muddy the waters on cranberry a little further,
I recently did a Goggle and found new study(S), maybe from UK that showed cranberry was not the concern that it has always be considered, I'm sending this message from memory, I did not print or save the reference, but if you are really trying to track it down
try a Google search and you will find it along with the many traditional references to cranberry being a concern and that you must either eliminate it or be very consistant with it. and always with a single study, take it for what it is worth.
The interaction between coumadin and cranberry juice has nothing to do with vitamin K, actually cranberry juice has the opposite effect of vitamin k when mixed with coumadin. It is thought to potentiate bleeding in two ways, by competing with receptor sites where coumadin is cleared in the liver and by altering the clotting factors, such as cox1. The result is that coumadin stays in the system longer thus potentiating its effects. Evidence is not clear exactly how coumadin and cranberry juice interact, but is not as simple as introducing extra vitamin k to the diet. Too much cranberry juice with coumadin increases the risk of bleeding, not like too much vitamin k in the diet will counteract coumadin and increase the risk of clotting. They have two different effects on the body.
From an acute care perspective I limit cranberry juice, especially if the person does not drink it at home for the following critical thinking:
Pt drinks 8oz cranberry juice per day in the hospital while Coumadin loading or adjusting, resulting in an INR of XXX when they leave. Patient then goes home, does not drink any cranberry juice at all thus resulting in a XXX drop in INR increasing the risk for clotting.
Yes it may not be a huge risk, but when it comes to Coumadin I do not mess with it. I had a patient once who was drinking Ginseng and St John's Wort tea at home for depression and came in with an INR of 10.4.
People will do as they like, but I am not going to propitiate the behavior to the best of my ability.
Tait
BBFRN, BSN, PhD
3,779 Posts
I thought most commercial cranberry juices were made from mostly apple juice with a little cranberry in it. I've had 'naked' cranberry juice before, and it's very bitter. It has to be mixed with other juices, because it's nasty all by itself.
http://www.coumadin.com/coumadin/channels/cmrcontent.jsp?BV_UseBVCookie=Yes&channelId=-11478#isi
Here's the official Coumadin website. It has a list of medium to high Vit. K content foods.