Taking Fragmin whilst on Warfarin

I have been given 1ml syringes of Fragmin for use in emergency. My Consultant said to take it if my INR drops below 2.0. At the moment it's 2.7 and I feel awful. I have never taken the Fragmin as a bit nervous it may thin my blood too much whilst I'm trying to raise my INR. I feel so bad just now and it will take a few days for INR to rise again. My INR range is 3.5 to 4.5. Has anyone else taken Fragmin with a similar INR of 2.7 and been okay?


9 Replies

  • Sorry to hear you feel so awful? Do you have any review due with consultant or GP? Do get them to look at your levels of B12, Ferritin and D, plus thyroid, to keep an eye on all that. It does sound as if your consultant has put a sensible plan in place for your, one familiar with others on here. MaryF

  • Thank you for your reply Mary. I was due to see my Consultant at Ninewells Hospital in Dundee last month. He left for a meeting early so I got sent to his colleague which was a complete waste of time! I am due back in October. However I have my annual appointment with Prof Hughes in September and I will ask him to recommend my NHS Doctors check the levels you mentioned,


  • Hi there and welcome.

    When I was on Warfarin, I used to take 5,000 IU Fragmin syringes the use if my INR dropped below 3.3, my target was 3.5 to 4.5 like you. I never had any difficulties with using the Fragmin concurrently whilst getting my INR back on target. Fragmin works in a different part of the clotting cascade to Warfarin.

    I'm now on Fragmin 15,000IU permanently and no longer on Warfarin.


  • That's interesting Dave as My Doctor just prescribed 10,000 IU / 1ml syringes. I am 5'6" and weigh 10 stone so maybe 5,000 IU could be used if INR is below 3. I will ask about this,


  • I take Fragmin if my INR drops below 3.0. I would also be taking above the usual warfarin to get the INR back up. As Dave says, they work in different ways. One of the main differences is that Fragmin (Heparin) works immediately whereas warfarin doesn't have an effect for a few days (2 to 3 according to Dr Hunt was in in the patients day videos?)

    Never a problem apart from bruising.

    Sounds like you may need to be towards the higher end of your INR range - seek advice from knowleagable medics.

    My target INR is 3.8 to 4.0 and I both over and undershoot at different times.

    Best of luck


  • PS. my Fragmin dose is 18,000 units a day when used - but I am a little on the large size!!

  • Thank you for your reply. It's reassuring to know you have taken both with INR below 3 and been okay,


  • When I was on Warfarin with a target range of 3 - 3.5, Prof Hughes gave me 10,000iu heparin (Fragmin) to take if I fell below 3. Now I am on Fragmin all the time. Personally I would never wait to go below 2.5 if on warfarin with APS. Perhaps check with your consultant if your symptoms are bad to see if you can start using the Fragmin.

  • That's interesting and good to know that Prof Hughes recommended taking it if below 3. I will be seeing him in September. Meanwhile my Consultant here (Scotland) recommends waiting until I'm below 2, by which time I'm very unwell indeed. I just hope I can wait until September or maybe I will be brave enough to try it, now I know others are safe. I self test and have very good control so this dip in INR does not happen very often,


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