I don't know about hives, but I've developed a rash on my face and on my lower back. I'm now off all meds except the warfarin (coumadin generic). The dr. gave me a cortizone pack and it cleared up, but now it's back and spreading. Nothing is helping them now.

I developed hives, and just felt awful after l was sent home from the hospital. Really bad constant headache too. My Dr put me back on Lovenox, gave me prednisone and all the symptoms went away. Same thing happened when I tried brand name coumadin a few months later. Some of us just can't tolerate coumadin. I'm a Lovenox lifer now.

Could be a Coumadin allergy. But probably the dye in the tablet . Have the Dr change the dosage of the tablet which will give you a different dye and if you have to cut the tablet down for the right dose, if it is less or take more tablets if you dosage is more. I had that trouble with the tablets that were orange (5mg) and now I have the 2.5mg green ones and just take 2 of them when I need 5 mg.

Thank you for the replies! I never considered it could be the dye in the tablet. So far, I have had 2.5, 5, and 10 tablets so I guess I would have to figure out which one could be causing the problem (if it is in fact the dye). Maybe they are being caused by stress and have nothing at all to do with coumadin. I also have had daily headaches which I never had a big problem with before.
Well, I go to the pulmonologist tomorrow (1st time since the hospital) so I will mention it and see whats he says.