Preventative Medications

I recently met with a neurologist for the 1st time regarding my migraines.  I was suffering with migraines twice a week at best and didn't have much success with beta blockers as a preventative.  He suggested I switch to Amitriptyline and it has worked very well for me.  During my last visit with my neurologist he told me that he would give me another month of Amitriptyline but that on my next visit we would go off of the amitriptyline to see how I react.  
I am at a total loss.  I finally get some reprieve and now he wants to take me off?  He said that Amitriptiline is not a permanent solution.  Can you please give me some advice if any of you have heard similar reactions from your neurologist?  

[Dr Santos]

Hi,
How are you? Amitriptyline is a tricyclic antidepressant which is used primarily as an antidepressant and anxiolytic agent but sometimes prescribed as a migraine preventive. However, tolerance to the adverse effects of these drugs often develops if treatment is continued. This is the reason why your doctor will take it off on your next visit. Talk to him and discuss your treatment plan to ease any worry. Take care and do keep us posted.