Thank you for all the information,
There are a few causes of tremor of thumb or hand.
Stress, anxiety, or fatigue are common causes.
If your work load is more that can cause it.
Normal aging can cause tremor.
Excessive alcohol, coffee can cause it too.
You need to look for those factors as they are easily avoidable.
Please try to relax.
If you do not feel improvement after correcting those, a neurological issue needs to be ruled out.
Parkinson's disease, MS, cerebellar diseases need to be checked for.
In that case, you would need an evaluation by a neurologist.
I hope this information helps.
If there’s anything else I can do, please let me know.
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