I had a DVT in my upper arm from a PICC line I've been on Warfarin for three months. can I quit cold turkey?

Absolutely not! I would consult my doctor immediately if there are reasons that you feel you should no longer take this medication. Warfarin is a medication that can mean the difference between life or death. I would not take this lightly. See your doctor, have another Vein ultrasound done to determine whether you can discontinue the use of the medication. Your doctor should be the only person to make this determination. Good luck.