Hi there ,
Welcome to Just answer !
Well, i believe it is not the drugs -- lithium or lamictal which has lead to this present condition of hers as she has been taking these drugs as you have mentioned for seveal years and such kind of delayed reaction is not poissble when she has sustained on these drugs quite well without any side effects having been developed over such a long period .
So, her present situation is not related to the side effects of either of these drugs , and it seems to be related to any other allergy , can be food allergy , which needs to be evaluated properly by a physician..
I hope this helps..
I wish you all the best..
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