I was diagnosed in November '22 with the CALR mutation and have been on 1500mg/daily of Hyrdroxyurea for a while to bring my platelets down from 1700 into normal range with an elevated white blood cell count the whole time, but then when it was eased up to 1000mg the white blood cell count went back to normal, but the platelet level worked back up into the 500's, so now I've been on 1000mg 4 days per week and 1500mg 3 days per week to see if that gets it back down without raising the white blood cell count back up. Going every 6 weeks for a blood draw now. No side effects the entire time, except for some bloating for the first couple weeks from the Hydroxyurea. I'm very active and have not lost any energy or had weight gain.