Letrozole affects Brain Function & memory in monkeys ......

My hands have been history for a couple of weeks now - left hand in particular - can't form a fist.  Very sore, stiff, achy, numb - initially morning & night but almost 24/7 now ..... and that's on Exemestane!!  It is quite similar to what happened in the first 6 weeks on Letrozole - but have been on Exemestane for 6 months now, so wasn't expecting it!  :(