I've been on warfarin for 2 weeks 3 days and have a target INR of 3 following instructions from Professor Khamashta. I've had three blood tests, the first was 1, the second 1.1 and the third today was still 1.1. The GP started me on 2mg warfarin then increased to 3mg , then 4mg and today advised alternating daily between 5 and 6mg. I realise everyone responds at different rates but can anyone tell me roughly how long it would take to reach my target INR. My GP is very sceptical about my typical APS symptoms and implied today that they are all in my head.