Cat licking more and side effects of tablets ?!

Question
8 nov 2014
I have a 9 year old ginger cat called jasper
I've never really notice before but compared to his brother he only has a very fine light covering of hair on his belly
Sometimes he makes his nipples sore in the area .
Last night he has made himself very raw over a 2 inch area of his stomach

9 aug 2014 Usual check up vet said he has a heart murmur ..he is incredibly calm and I was quite shocked

This lead to a test of hyperthroidisum showing t4 as 157 apparently that's massive
After 3 weeks of 2x5mg felimazole tablets I took him back as his lumph nodes were up in his neck

23 sept 2014 Did another blood test and he is was t4 NOW 6.44 so under average
Tablets came down to now 2x2.5mg

30 oct 2014 3.5 weeks another blood test can't remember but think it was about t4 was 6 so tablets now 2x1.25mg

Today 8 nov I have called the vets as like I said above he is raw on his stomach seams to be itching more and his lymph nodes in his neck are up again.
Just off the phone to the vet who now says 'lets see if he is proper hyperthroidisum take him off the tablets for 3 weeks and lets do a test see if his licking stops and his lymph nodes in his neck go down

What thoughts do you have !?? I'm thinking of the food for this condition (I have 2 cats so need to think of managing this ) and not quite sure what advice I should follow ?!

Answer
Did he lick himself and have allergies prior to starting on his medications? What flea control is he on? Usually the itching is just facial itching as a side effect of the methimazole. I don't want to interfere with your vet's care, as your vet has more information to work with than I do! I will try to give some additional information about allergies though if that's what you think it is.