First week on warfarin, a couple things I've noticed

[cewilk]

Got my mechanical valve last week and have been on warfarin for about a week now. Currently a bit low on the INR on my last blood test, but I'm alternating between 10mg and 7.5 mg doses each day until my next blood test. This week I've only noticed a couple things that I'm not sure I can attribute to warfarin or not. I've been having some pretty mild-moderate headaches that have been pretty persistent throughout most of the day, but when I stand up from lying or sitting I get a pretty extreme throbbing pain that lasts a couple seconds. Also, I've had the weird 'splotchy image things' that seem to be in my peripheral vision (like the weird little things you see in your eyes maybe after a bright camera flash) that randomly appear and last for several minutes. Finally, I've gotten pretty dizzy on a few random occasions and had to actually hold on to something or sit down.

So just wondering if anyone has experienced anything similar! Thanks.

 

[tom in MO]

I would guess these are after effects from surgery, not related to warfarin. Peripheral vision "ghosts" and some random dizziness all happened to me after surgery but do not happen to me now...and I take warfarin then and now. I did not have the headaches, but would have if there was any allergy stuff going on. It's only been 7 days out from probably the most severe trauma your body will ever have.

 

[djacq]

It seems many have mentioned visual issues after surgery. Mine were peripheral artifacts and lasted for some time, similar to what you describe. Headaches, I'm don't remember having but may be an after effect from the anesthesia. Headaches and visual problems can also indicate other problems also so hope you call your doctor. I hope you progress in your recovery quickly and keep us informed.

 

[Freddie]

Are you taking any other drugs besides warfarin? Beta blockers (Ramipril sp?) can cause dizziness.

but when in doubt get it checked out

 

[big_L]

I'd agree with the opinion that the symptoms are a surgical artifact. I'm 17 months post surgery and I have absolutely no symptoms from the warfarin or the surgery, other than a scar and the valve click.

 

[MrsBray]

Aural migraines (wavy lines in the vision field) and lower-than-I-was-used-to blood pressure made for some interesting moments after I came home. I figured it was because my brain was getting much better blood flow than before surgery!

 

[pellicle]

Hi

Got my mechanical valve last week and have been on warfarin for about a week now.

glad to hear you're up and around ...

This week I've only noticed a couple things that I'm not sure I can attribute to warfarin or not. I've been having some pretty mild-moderate headaches that have been pretty persistent throughout most of the day, but when I stand up from lying or sitting I get a pretty extreme throbbing pain that lasts a couple seconds. Also, I've had the weird 'splotchy image things' that seem to be in my peripheral vision (like the weird little things you see in your eyes maybe after a bright camera flash) that randomly appear and last for several minutes. Finally, I've gotten pretty dizzy on a few random occasions and had to actually hold on to something or sit down.

I wouldn't attribute those to warfarin either. I get the migrains when I've been sitting in a bad posture or have been stressed. In the past I used to go to a chiropracter from time to time and they (well a few of them) said that those visual disturbances can be related to back and neck issues.

If that's true (and there seemed to be a linkage to me) then it seems reasonable that your back / neck could just be "out" due to all the pulling, shoving , arms streched out stuff that you went through during the surgery in combination with all the strange muscle tensions you must be undergoing with holding your posture different, moving different and being generally uneasy.

My experience is that it all came back to normal over a few months and by 6 or 7 months it wasn't any different to before the OHS

I'm also going to bang on my usual drum and suggest that where ever possible try to maintain an even dosage, I have problems with alternating doses. For instance when do they take a blood samples in relation to you having the 10mg or 7mg dose? If you actually take daily measurements you'll see that the INR responds quickly to warfarin. Its commonly stated that it doesn't make a difference, but when you take measurements it does.

Best Wishes

 

[epstns]

pellicle - if cewilk is the (victim) patient of the same sort of home care nursing I had, they only test INR weekly. So, they may believe that their recommendation to alternate doses is OK, if they always test on the same dose day. I am not sure - you probably know far more than I about how the body usually reacts to differing dosages.

I did, however, have a lot of trouble getting my INR up to target range. I only took warfarin for 3 months, but it wasn't until nearly the end of the time period that I was reliably in range. I guess there were too many things changing and getting back toward normal in my system for things to stabilize.

Other than that, the only side effect I ever noted was that my hair thinned noticeably while I was taking warfarin. The same happened to my mother, to it may be a genetic propensity for the warfarin to affect some of us that way.

 

[Cardinal fan 61]

I had headaches for about two weeks after ny surgery. I saw the "floaties" and color flashes. They all cleared up in a couple of weeks.

 

[tom in MO]

Alternating doses is common. They did it with me.

Don't know why Pellicle's response to warfarin is more dynamic, but that's not the case for me or in the majority of literature I have read or what I have been told by my health care providers.

In addition, there is no "right time" of the day to measure your INR. You don't have to do it before or after dose, or at the same time. I got that from my INR clinic and also the meter manufacturer.

 

[pellicle]

Hey Steve

I think that the three month period for stabilisation is about right.
Personally I think testing weekly is quite sufficient, I only test more frequently when I have a research goal in mind (such as observing how quickly one responds to changes in dose.

Just because something is "done that way" does not make it right. It took decades to stop doctors treating gunshot wounds with boiling oil to cauterize the wound. One of the early studies revealed at such treatment was strongly correlated to gangreen and then amputation.


The half life of warfarin is some thing like 20 hours, but it is a range not a fixed number. This means that in person X it may be 18 hours and in person Y it may be 40 hours. It depends on your genetics (well published and well understood for over 10 years now).

Change does not come quickly to the medical world and slower it seems in the minds of the general patient population. People seem to love to "know things" but seldom explore personally instead just repeating "common knowledge"

From mims
The effective half-life ranges from 20 to 60 hours with a mean of about 40 hours

If one were to think about this question of dose and speed of reaction logically then since adding vitamin K can restore coagulation in a few hours it would be logical that warfarin can disrupt it nearly as quickly.

---

PS: From the Australian Society of Thrombosis and Haemostasis
https://www.mja.com.au/journal/2004/...c71e2c6214dc5d

The effective half-life of warfarin ranges from 20 to 60 hours, with a mean of about 40 hours. The duration of effect is 2–5 days.5 The drug is completely absorbed after oral administration, and peak concentrations occur within 4 hours. The elimination of warfarin is almost entirely by metabolism, with very little excreted unchanged in the urine and bile. Metabolism occurs mainly in the liver, involving the cytochrome P450, and in particular the CYP2C9, isoenzyme

Initial increases in international normalised ratio (INR) are typically noted 24–36 hours after giving the first dose of warfarin

so it seems my observations fit within well known (published) understandings of the kinetics of warfarin

 

[pellicle]

Hi Tom

Don't know why Pellicle's response to warfarin is more dynamic, but that's not the case for me or in the majority of literature I have read or what I have been told by my health care providers.er.

Can you show me something that says there is a lag? Or can you only show things which say it takes time to stabilise (quite different).

Ibelieve that in the main metabolism of warfarin may smooth out some wrinkles of INR to alternating dose but can you tell me what is wrong with having the dose regular? Certainly I can tell you what is wrong wwith having it irregular.

Obviously you would afree that wildly variant doses (say 15 , 1) would be "wrong" so why draw the line and say 7 10 is not ideal either.

Have you done dailyINR mreasurements your self?

 

[pellicle]

Historical Caveat

I earlier raised the issue of medical practice taking time to change, this was topic raised during my first year in microbiology / biochem degree.

(ref link)
A surgeon called Pare noted in works he published (1545) that patients treated with boiling oil did far worse than those treated with a paste of onions. Being of not the right breeding I'm sure led to his work being dismissed, However his work was later substantiated by the Surgeon to the Pope (Giovanni Virgo) from about the same time. Virgo wrote:

Beyond my hopes I found those on whom I had put the digestive dressing feeling little pain from their wounds which were not swollen or inflamed, and having spent quite a restful night. But the others, to whom the said oil had been applied, I found fevered, with great pain and swelling around their wounds

The American Civil war was some centuries later (1861) yet at that time it was still common surgical practice for Army Surgeons to tip boiling oil onto gunshot wounds to cauterize them. The amputation rate was tragic.

Medicine seems to be quite resistant to 'evidence based' practice, and the clinicians who are simple souls taught to simply regurgitate policy are often also complicit in the perpetration of poor practice.

 

[cewilk]

Since I posted this last week I haven't had any more of those symptoms. Guess I just got a little overly-concerned since I'm new to warfarin. My INR was 1.8 two days ago so now on 10mg all week and maybe I'll hit my 2.5-3 range next visit or two.

 

[pellicle]

Lots of changes in a short me and lots of medications and trauma recovery on your plate at the moment. I think your reaction and concern is quite common.

I was worried in my first months on warfarin. Always worried about my dose and about my reactions to foods. My lovely wife sent many hours researching whatI should avoid eatiing.

It was over a year before I discovered this place.

Also don't fret about what levels of warfarin are needed, the INR is the only goal and the range of warfarin required by people varies quite a bit.

 

[ajc1991]

I would also agree that these are after effects from surgery rather than Warafrain. The week after my surgery there was something that would happen about 4 times daily, and this was when I'd see a little round dot of light out of the corner of my eye, and when I tried to chase it by moving my eye it would go away. I experienced occular migraines (where you get that zig zag flashing light in your eye) almost daily after surgery. I dealt with ocular migraines before surgery but they weren't as persistent as they were the week after my surgery. I no longer have gotten the ocular migraines since. I've also been on Warfarin, for two weeks now. Mys surgery was on Jan 15th.

My INR last (from this past Monday) was 2.6. My goal is 2.5-3.5. My INR is climbing quite nicely and was doing well in the hospital as well. I'm currently taking 10 mgs daily until I get my blood tested again next Monday.