Does any one else have any experience of this? Was diagnosed with Hashi's last year and am on 75 mcg levothyroxine. Over the last couple of months I have noticed my pulse rate becoming slower - at rest it ranges from 52-56 bpm. I asked my GP for a retest of TSH and T4 and today they tell me these values are "normal" i.e. within the reference range (receptionist did not know exact values). Have made appt to speak to GP about this as I suspect values are close to being outside of the range. Has anyone else been through this?