Great question! Diamox causes numbness and tingling (and sort of crawly sensations), especially in the hands and feet for about two weeks, and then it stops. I DID take it once after years of not needing it, and felt these sensations on one side of my face, and in patches throughout my body. It scared me, because I sort of forgot what this paresthesia felt like! Sure enough, it went away, no harm done. Of course, no one can tell you the reason YOU experienced what you experienced, but please know that I’ve seen some FUNKY initial responses! Oh, if your CO2 is low, or if your pressure is crazy high, you may not notice much effect, if any. Did you check your CO2?