Brief Answer:
It can be inner ear issue

Detailed Answer:
Hello dear, welcome to Ask a doctor's service.
I read your query and here is my advice.

I believe this loss of balance may be related to ear issues either inner ear infection, benign positional vertigo or Meniere's disease.
Do you have other symptoms of vertigo when you move head , when you try to stand up, earache and nausea?
I think you should get further examined visiting an ENT doctor.
In this case taking betahistine can be useful.

Also it can be a side effect of antidepressant , sedatives and anti anxiety drugs.

Hope I have answered the question.
Let me know if I can assist you further.

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