I have been tested for underactive thyroid but was negative. Still lethargic. Why?

Iron. Have you checked your iron levels? An iron deficiency or small GI bleed resulting in low iron levels can be a cause of fatigue. Ensure you're also properly hydrated as well with at least 64 oz of h2o.

Related Questions

I have pcos, an underactive thyroid, suffer from anxiety and depression. I feel lethargic, body hurts, getz lethargic, numb body...What could this be?

Get a consult. Find a good psychiatrist who knows the interactions between medical illness and psychiatric illness and work together on this issue to what the answers are. There are probably several possible answers. Good luck. Read more...

I have lump in throat husky voice fatigue neck stiffness. Brain fog. Bad memory Mum has underactive thyroid. Dr says not my thyroid. Could he be wrong?

Testing. I do not know if he is wrong. Was there any testing done such as blood work or an ultrasound of your thyroid, etc. Infectious process is always a possibility too. Be persistent and get follow-up appts if they continue. Good luck. Read more...
Thyroid tests. If he measured your thyroid hormone levels with blood tests, and they were normal, then he is probably right. Read more...