My hyperthyroidism was masked for a while by marathon training and pre existing mental disorder (bipolar), and disordered eating. My heart rate was consistently elevated which can be a sign of overtraining, I lost a couple of kg of muscle, I took more and more 'time off' exercise but I had the worst DOMS particularly in my quads, also upper arms. My mood felt like it was going up but I was in a constant state of apprehension and often woke with my heart racing, galloping, and my fists and jaw tightly clenched. Had a pretty bad tremor and constant stream of soft 💩 but we had increased my lithium to bring my mood down and these are known side effects of lithium. Every so often when they check lithium levels (once or twice a year) thyroid function is also tested and one day I got a call from my GP asking me where I was and could I get to the surgery within the hour 😮 I was so scared!
GP had already spoken to endocrinologist and they started me on carbimazole and propranolol right away, she examined the (tiny) goitre that I'd thought was a sore throat from vomiting (on purpose, but I could not stop eating and I didn't want to get fat 😳). Went for a scan to check for nodules or whatever, had none of those, they tested for absolutely everything and endocrinologist decided it was 'probable' Graves although having the antibodies isn't diagnostic, it's only really the eye involvement which confirms it I think. Carbimazole kept going up, I struggled to take it, radioactive iodine didn't work because lithium suppressed its uptake. There was a period of indescribable fatigue, I couldn't walk a mile I was so out of breath, then I couldn't walk a quarter of a mile. I fell asleep in the gym. I couldn't get up off the sofa sometimes, it was like something pinned me there. This didn't last long at all! I piled on a whole stone of fat really quickly but it did disappear almost as fast.
Things that helped me:
The dreaded carbimazole (it's absolutely fine)
Getting as much rest as possible
When people suggest you will feel better if you fight the fatigue and go out/do something tell them to Fuck Off
Eating lots of everything
Fancying my endocrinologist- don't think have ever missed an appointment at thyroid clinic with him 😃
In some ways I'm better than before now? It's about 3 years on, I've got my head round the fact that I could need the surgery at some point (lots of people go into long term remission but they have no way of telling who yet). My running fitness is back, my only grievance is that I never experienced the heat intolerance and continued to be painfully susceptible to the cold throughout.