50mg Imuran increment make difference?

Hey Gang - I have been gone for awhile from our website, and doing well on the whole. Got off pred 3 months ago and Imuran seems to have helped me. i was put on Imuran about 5 months ago, but my GI increased my dose slowly, over time, to make sure I could handle it. I am now taking 150mg, but only added the last 50mg about 2 months ago, so I am only getting the benefits of about 100mg (it took 4 months for imuran to start working for me, so I feel pretty confident that it takes my body awhile to start benefiting from the drug). i am starting to see some symptoms again, and of course my mind is now spinning, worrying that Imuran will fail me. but, then I realized that maybe I just need this next 50mg to kick in.... so, what i am wondering, for those of you on Imuran, have you seen a difference in the effectiveness of the drug at a different dose? in other words, do you feel there is a substantial difference between 100 mg. and 150 mg? I am hoping the answer is "yes," and my GI certainly thinks that 50mg increments make a difference, but i wanted to check you with guys since you have the actual experience.....

as always, many thanks and I hope you all are well.

well, I went from taking 100mg for two weeks to taking 200mg and have been on 200mg for 4weeks now. I don't notice anything different....(have been on azathioprine for 6 weeks in total).