Sensitivity of Dosing

[Cameron]

Team,
I have been running at a dose level of between 70-77mg/week for some 7 months since surgery on 22 Jan 2009. I home test weekly and have found that I seem to be quite sensitive to relatively small dose changes - 70mg seems too low as I trend down, and 77mg is too high as I trend up. I have tried alternating from 10 to 11mg/day to get a weekly dose of anywhere from 73 to 74mg/week but still get trends one way or the other. I think I read elsewhere that the bigger the dose you are on the more sensitive to changes you are. Currently I am not comfortable enough to go to 2 week testing when I see how my weekly numbers can vary. My preferred range is 2.5 to 3.5 and I have been trying for 3. Over the 7 months I have come up from chronically at the low 2's to now high 3's but seem to vary with very small dose changes. I don't mind testing every week (cost of a high end coffee!) but would like to know if this level of sensitivity to a few % points of dose change is to be expected. Do I have to split a 1mg to get 73.5!!
Thanks,
Cameron

 

[Bina]

Hi Cameron!
I am on a very low dose (18 mg) per week and am also very sensitive to changes.
Adjusting by 1mg per week is a big thing for me and I rarely do it.
When I want to tweak a bit, usually when my INR is a bit high at 4, then I just eat more broccoli.
It's YUMMY, nutritous, and it brings my INR down to 3.2 over 2 weeks.

 

[dick0236]

Two weeks ago I tested 3.4, today I tested 2.6 (last nite I had a big helping of "greens", so maybe, or maybe not, that was the reason for the drop).....all on the same dose of 5mg/day, 35mg/wk. For me, these swings are no big deal. It is what it is, and as long as I stay in, or closed to, my range 2.5-3.5 I make no change. Continue to test as often as "what makes you comfortable", but I would hesitate in micro-managing your dose, such as 1mg changes on 70mb/wk.

 

[geebee]

Are you making changes in your dose for being in the "high 3's"? If so, that might be the issue. With a range of 2.5-3.5, anything under 4.0 is in range. Unless you are under 2.5 or over 4.0, I would not make any changes at all.

 

[lance]

I totally agree .....................

I totally agree .....................

Geebee, that's what I'd do.

Cameron, We're on the same dose 11, 12 11, 12, etc. TWD 72-73. Recently I had an early morning reading of 4.2. My manager reduced my daily dose by 2 mg (1 day only) and then I continued alternating 11,12.

Later that morning I was in the ER so they had to check my INR again. It was 4.0 in the lab and horror of horrors attending doctor looked like he thought I would bleed from every pore. He advised dropping warfarin for 2 days, a total of 21 mgs. This man was extremely agitated when I told him that wasn't going to happen. The 2 mg reduction was certainly enough for a 4.0 reading.

Glad to learn you are doing so well with your home monitoring.

 

[netmiff]

lance, that happened to me, too, in emergency; INR was over 6, I confess, but they had not fed me for over 12 hours, and I was almost totally immobile the whole time. When I was being discharged, he told me to stop 3 days dose, I said NO; after a little while, I heard mutterings about vitamin K injections, so I simply said OK, OK, I will hold doses for 3 days - trust me, my fingers were crossed behind my back! I just wanted out of there to get something to eat!

 

[lance]

holy moly Jeanette!

3-day withdrawal and/or a vitamin K-shot too. Even for a 6 reading that seems a little draconian. Do you remember what action you took to lower it? Once mine was at 6 but it was so long ago I can't remember what we did. My manager never withdraws a full dose of warfarin preferring to use 1/2 daily dose for a day or two instead. She is so concerned about missed doses that I am to page her immediately should I miss one. She said that Vit. K does funny things and prefers to not use it. Something else, too. My target is 3.5-4.0 not 2.5 to 3.5. Even with this narrow range with the help of XS and weekly testing my INR is kept there 90% of the time. Heaven help me should I have to explain that in an emergency situation.

Just think how much better off we all are for the knowledge provided on this site. We truly are the lucky ones.