INR & Flying

[Davros]

Hi,

I have experienced dramatic changes (Increase of INR) with flying. This isn't because I take my Warfarin at different times of the day because I'm in a different time zone. I take my dose at GMT +12hrs every day.

This seems a bizarre condition but has anyone else had this experience?

 

[dick0236]

I have flown many times, within the USA, including Hawaii and Alaska, and internationaly too Europe. I have never noticed any problem with INR as a result of any trips.

 

[Greg a]

If you are experiencing different time zones could it have anything to do with meals served in flight? I was on Warfarin such a short time that I can't be of much help then on the other hand ......I think dick was on it before the rats

sorry Dick I could not resist I TRIED BUT JUST HAD TO PUT IT OUT THERE

 

[Protimenow]

The only thing I can think of is if you made major changes to your activity levels during travel. In other words, if you're normally very active - heart beating quickly for long periods of time, sweating, etc. - and sitting locked into a seat on an airplane brings your activity levels down closer to zero - then PERHAPS this change in activity can have an effect on your INR. A faster metabolism would probably metabolize the warfarin more quickly than it does when you're not active. A higher dose taken to compensate for the faster metabolism could result in a higher INR when your metabolism slows down. Of course, this is all a guess, but it's the only explanation I can come up with for right now.

I don't think anything directly related to air travel changing INRs has been published (of course, I could be wrong about this).

 

[dick0236]

......I think dick was on it before the rats ]]

:tongue2:I don't go back quite that far:biggrin2:. I saw a report recently that President Dwight Eisenhower was on it back in the '50s.

 

[Lily]

Hi,

I have experienced dramatic changes (Increase of INR) with flying. This isn't because I take my Warfarin at different times of the day because I'm in a different time zone. I take my dose at GMT +12hrs every day.

This seems a bizarre condition but has anyone else had this experience?

Over the years I have occasionally read of others here on ACT who had high INRs for no recognizable reason following/during international travel.

Flying is not a non-issue; it does place some demands on our bodies, and in a number of different ways. It can dehydrate a body, and your oxygen is reduced, even in a pressurized cabin. Also, do you ever take any medication before flying that might affect your INR, motion sickness pills or decongestants?

 

[Davros]

Hi Lily,

No other medication. Last time was a few months ago on a 12hr flight back from Thailand. Other times have been a 24hr flight from Europe. My INR increases from 2.5 to over 4 with no change to the dosage. Takes a few days to come down again. Just one of those things I put down to flying. Perhaps it is the cabin pressure.

Mike

 

[Protimenow]

This sort of validates my theory. Are you usually pretty active when you aren't sitting in a seat at the airport for a couple hours, then another 12-24 hours in a cramped airplane seat? If the dose of warfarin you take is predicated on a lot of activity, and then your activity drops for many hours, it might be possible that your body isn't metabolizing the warfarin (or doing the other anticoagulation things) that you normally do. Also -- if your diet when on the ground includes a lot of greens and other Vitamin-K rich foods - then not having the same amount of Vitamin-K can also result in an increase in your INR.

Just a few thoughts...

 

[normofthenorth]

I got my INR tested in Whistler BC this past Thursday. I'd flown Toronto-Vancouver ("only" 4-5 hours in the air), then skied 4 days, getting WAY more cardio exercise than I have since OHS/AVR. My target range is 2.5-3.0, and my previous two readings (1-2/week) were 3.1 and 3.0. This one was 2.9, just about what I would have guessed. (I've backed off the dose a smidge since the 3.1.)

Maybe the exercise lowered my INR the same amount as the plane flight raised it??

 

[bethann]

yes,

this has happened to my son. I agree that it has to do with activity level. I notice his inr increases when he is less active (like our recent snow weeks!). He has very high metabolism and alternates 9-10mg of coumadin. This may make him more likely to experience this fluctuation.

The other thing that could affect your inr is dehydration. Long flights especially are dehydrating, so the less water you drink, the more difficulty your body has flushing the coumadin from your system.

I don't think I have enough information to predict the changes at this point, but will be careful to monitor him a bit closer when we take long flights in the future.

Bethann

 

[catwoman]

I fly quite a bit -- have flown up to 4 weekends back-to-back.
It's not FLYING that can wreak havoc on your INR, but the change in your normal schedule -- not eating meals on time, not eating your usual diet, not taking your meds on time or even forgetting a dose. I take my warfarin with breakfast, which is usually about 6:45-7 a.m. CST. But when I'm traveling, I don't always eat breakfast then.
Bethann mentioned dehydration from flying, which can cause your INR to increase.

When I travel, I work harder to keep my usual schedule, diet, etc. Most of my travel is for cat shows and I'm at someone else's "mercy" if I'm judging. Some hotel restaurants are great, some are average and some are just crappy. So, I've learned to eat soup and salad, or a salad and an appetizer that can make do as an entree.

BTW, the highest my INR has been in the last 6 or so months is 4.1. It was 3.8 two weeks ago, but most of the time it's 2.7-3.5 (range is 2.5-3.5, my cardio wants it at the higher end).