Warfarin overdose

[Redneck49]

Can you help me my husband takes 8 mgs of warfarin every night and he has just taken another 8 mgs by mistake I phoned out of hours go and he told me the hospital said it was ok for him to wait til morning to have his inr checked but he hasn't been feeling well this couple of days and I'm worrying in case anything happens to him

[JaneFinn]

Hi redneck, I’m afraid that I’m not going to be much help as I don’t take warfarin myself, but I did want you to know someone is up &has seen your post and is thinking of you x

It’s so horrible worrying about someone we love, isn’t it? First of all I’d say it’s great that you phoned for advice from the right people and that they said it’s fine to leave it til his INR can be checked tomorrow. This totally tallies with what I’ve read on here where people have taken their warfarin twice by mistake and have been advised there is absolutely no panic about it, because warfarin adjustments happen over quite a prolonged timescale and can be re-adjusted in the same way.

However I think what’s preying on your mind is that your husband hasn’t been feeling well anyway in the last couple of days? In my limited knowledge I’d say it’s unlikely to be warfarin-linked, or affected by the extra warfarin ... but you and me we’re not doctors. And you ARE worried. And doctors are there to advise. So if I were you I’d ring the out of hours dr again and explain what symptoms he has and that you’re worried. And ask if he’s more at risk of it being serious because of the warfarin situation. Hopefully they will just be able to reassure you! But if I were you I wouldn’t be happy til I’d at least checked it out. Unless he’s feeling ok & happily asleep by now

Good luck... and best wishes to your husband. Please let us know how he gets on xx

[Redneck49 in reply to JaneFinn]

Thank you so much for your kind thoughts he has an appointment this morning to have his inr checked

[JonathanPittsCrick]

Hi Redneck,

You don't have to worry – warfarin takes a long time to work (a week or two) and a long time to stop working. So it really doesn't matter if you take two doses at once and miss the next one (it wouldn't even matter if you saved them all up for a week and took them all at once). So long as your total dose for the week is about right, the details of how and when you take it make little difference. The reason for taking it regularly every day is just that it's easier to remember that way.

So if you miss a dose just take double the next day; if you take a double dose by mistake don't take one at all the next day – and then carry on as normal.

VERY IMPORTANT: this does NOT apply to the new oral anticoagulants which have to be taken as near as possible to every 12 or 24 hours (according to the type) and if you do miss one you should NOT take a double dose to "catch up".

[Hidden in reply to JonathanPittsCrick]

As a warfarin patient that is really reassuring to know .Thank you!

Perhaps I could add though that as a self tester I notice difference in readings whether from dietary changes or dosage alteration in 3 days.

[BobD Volunteer in reply to JonathanPittsCrick]

Thank you for that Jonathan. Good to have an expert tell us things occasionally.

[JaneFinn in reply to JonathanPittsCrick]

Thank you so much for bothering to reply like this and help us all understand this stuff. Really grateful for your expertise.

[ILowe in reply to JonathanPittsCrick]

I am not sure I agree with some of your statements about warfarin. I agree that warfarin is sluggish, for technical reasons usually talked about in terms of half life. I also agree that it is good to look at the picture in terms of a week. It would matter though if you took seven days in one go. Just look at the medical literature on initiating people onto warfarin. Decades ago the policy was to start with a high loading dose then drop to a guessed lower dose. But that created dangerous high peaks before settling down. Nowadays the policy is to start with say 5mg daily, and slowly increase or decrease.

You say "If you miss a dose just take double the next day". The official advice in my little yellow book (which I still use) is "Don't take an extra dose of anticoagulant if you are unsure if you have taken your tablets". Thinking weekly, but allowing for elimination rates, a better way if you knowingly missed a day would be to either ignore it (official advice) or to boost the next few days by about 60-80% of the missed dose. So, if on 8mg, missed day, boost with 11, 10, 9, then 8mg as usual.

[opal11uk]

I agree with the posts before, as a previous Warfarin taker, so try not to worry he should be fine. If he isn't feeling very well in general then get him to see his GP.

[NannyChickens]

And for the future buy him a dosset box and fill it weekly. It is absolutely the only way I can remember whether or not I have taken my pills morning and night.

[MarkS]

I have experimented with missing and doubling doses with warfarin in the past when I had some spare INR strips that were about to go out of date. Missing warfarin one day dropped my INR by about 0.3 or 0.4. Doubling the next day brought the INR back to exactly where it should have been. You of course did this the other way round, so I would have thought the doubled dose would increase INR by 0.3 or 0.4, which would then drop back to where it should be after you miss a dose for 24 hours.

I also take a dose of 8 or 9 mg. I guess with your 8mg dose, you have one pink (5mg) and one blue (3mg). I mark up the foil above each pink tablet with the day I'm supposed to take it (M, TU, W, TH, etc.). That saves fiddling with a box. It's worked for me for nearly 10 years with no unintentionally missed or doubled doses.

[ILowe]

I hate swings. Double-dose then miss-a-dose seems like a way to encourage swings. Warfarin is very sluggish, but swings do happen. Double-dose will create a peak roughly 2 days later, and missing a dose does not compensate. A large part of the extra 8mg will be quickly excreted. I would take 4mg the next day, then 6mg, then the normal dose.

I have done this on myself, and a few days later I was still in range.

[Gracey23]

Can someone tell us the protocol on taking Eliquis. I’m taking a tablet every 12 hours as directed. What happens with missed dose or if you take extra by mistake? I have pills in a special case and alarm set on my phone but it’s still very concerning to mess up! Such good advice given on Warfarin this morning thought I’d ask for us on new anticoagulants, thank you!

[beardy_chris in reply to Gracey23]

It is, of course, always best to take your Eliquis at the right times. I asked several cardiologists just how accurate you needed to be. The best answer I got was along the lines of "Within one hour either way, no problem. Within two hours either way, very minor issue. Within four hours either way, some degradation of protection". Bearing in mind that we are generally talking about the reduction of an already low risk, don't panic if you miss a dose but it's better not to!

If you are having surgery, you will be advised to stop taking Eliquis for 48 hours - that is not a serious issue. So, overall, relax and do your best to take it at the right time!

[JaneFinn]

Hi redneck, just wondering how your husband is feeling now? Hope he got on well today. X

[BernardS]

A bit late but I find that marking each tablet with the initial of the day of the week in a fine point permanent marker pen works just fine