Brief Answer:
follow the advises... observe how you stay after this...

Detailed Answer:

Hello,

Firstly, try to check if it's only happening in front of the larger audience or also happening when you're speaking among friends and family.

Secondly, also try to notice if this is only happening once in a while or recurring on a daily basis...

If happening rarely, then it's probably attributed to stress...Take your time and relax in that case...ensure to do some stage preparation before delivering the speeches, practice deep breathing, speak slowly, always think and organize the thoughts before speaking, try to be confident in front of the audience (the stage preparation beforehand will help)...

Try to avoid triggering factors like excessive use of caffeinated drinks (not more than 2 cups of coffee/tea per day), avoid fizzy/sugary drinks/alcohol/smoking in the first place...

Start doing Meditation every day morning for about half an hour...it's highly effective for proper focusing if practiced properly and regularly...

Now, if you notice this is happening on daily basis or while speaking among friends and families as well, then the next step is to consult a Neurologist(specifically) for a thorough clinical examination (Systemic Neurological examination) along with lab-investigations (CBC, Electrolytes, Thyroid function test, Vitamin B12 and Vit D3 levels) as well as few performance tests (eg. drawing a circle, straight lines, holding a glass properly, drinking from it without spilling, walking in straight line etc.).

These will mostly rule out if there are any significant neurological involvement, and based on their result, medication like Beta-blockers (Propranolol) can be initiated to observe how you stay (remember, medicine is not the first choice here, first the exact cause has to be detected after thorough evaluation)...

There're other alternatives like relaxation therapies, psychological counseling, behavioral therapies by Psychologist but that should be decided by the Neurologist based on the clinical findings...

Hope this is clear, feel free to revert back in case of any doubts...

Take Care
Kind Regards

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