Noticed that ive had a lot of muscle weakness since on levothyroxine. Looked up drugs that affect and cause muscle weakness but levothyroxine isn't mentioned although other thyroid drugs are. Another cause for muscle weakness is inflammation which I assume would be associated with cortisol and would I be right to assume that maybe that's why patients adrenal functions should be checked before starting levothyroxine. I'm not aware that mine were checked but would I be correct in assuming that maybe due to my constant moan regarding muscle weakness that either my gp or endo should investigate and advise me or offer me a solution. Ive tried anti inflammatory, turmeric and some expensive enzyme made from the silk worm but none are effective or advisable long term. Ive noticed that when taking a break from levo the symptoms are reduced and my muscles can again engage in activity without pain and reduced strength but without levo my energy levels decline. I feel that I have a choice good energy with wasted muscles or low energy but strong muscles. Does anyone one know a better solution.
Energy or Muscle, who can choose.: Noticed that... - Thyroid UK
Energy or Muscle, who can choose.
You say : "Another cause for muscle weakness is inflammation which I assume would be associated with cortisol " Inflammation in the body occurs if you have Hashimotos Thyroiditis. Have you had your thyroid antibodies tested? I discovered in January 2017 via a private blood test that I don't have 'run of the mill' Hypothyroid, I have Hashimotos. Also I discovered in June 2017, again via a private test, that I have the faulty thyroid gene DIO2, which means I can't convert T4 into the usable thyroid hormone T3. I felt absolutely awful on T4 for the first fourteen years following diagnosis of Hypothyroid. But there were two things that even Professors of Endocrinology missed - 1. my thyroid antibodies were high =- inflammation, 2. My faulty thyroid gene so absolutely have to take T3. Since I have known these two factors, I have fully recovered.
Magnesium supplements can help with muscle problems. But you also need to know that your folate, ferritin, vitamin B12 and vitamin D are at the correct level. When was your last thyroid blood test?
Ive used magnesium ect. muscle weakness is listed as a side effect not a symptom. doc diagnosed hypo, endo thought I had graves. Don't fig, weird world we live in. Glad your well and sad that it took so many years to fix you. Thanks for the reply marigold22
I don't trust even what Professors of Endocrinology say now.... one nearly killed me. !
when I was first diagnosed I read a book by two endocrinologists from the states, they said don't touch generic versions of thyroid med but that's all the uk offer, are they saying don't take any ??? I'm so confused. levothyroxine and levothyroxine sodium have different structures c15H11I4NO4 and C15H10I4NNa04, the first one scares me because it has NO4 which is a actinide nobelium which is radioactive. I don't think we should be taking stuff like that.
All actinides are radioactive and release energy upon radioactive decay; naturally occurring uranium and thorium, and synthetically produced plutonium are the most abundant actinides on Earth. These are used in nuclear reactors and nuclear weapons. Uranium and thorium also have diverse current or historical uses, and americium is used in the . got this from wikipedia
Muscle weakness 
Muscle strength/pain
Worsening insomnia can anyone help?
