There’s a small portion of us that have really bad reactions to aromatase-inhibitors. I took one 5 months ago and after a wild panic attack 2 days later, I literally could not sleep for almost 2 months, after sleeping like a rock for 31 years of my life. Had some other wild symptoms, crazy heart palps, muscle twitches etc. Never experienced anything like this in my life. I’ve made considerable progress but still not my old self, getting maybe 4 hours of sleep a night and my head has this weird effervescent feeling.