Brief Answer:
ginkobiloba extracts.

Detailed Answer:
Hi, thanks for your query.

Tinnitus is a symptom with many underlying cause. Treatment varies according to the cause. Many systemic causes like hypertension, diabetes, brain haemorrhage, stroke, inner ear disease like meneires disease, BPPV, labrynthitis, viral infections are the common cause.

Commonest local cause are wax in ear canal-- treatment wax removal.
Eustachian tube dysfunction causing negative pressure in the middle ear, - treatment is decongestant tablet and nasal drops.

Inner ear disease - ginkobiloba extract, Oto-sclerosis - Stapedectomy surgery.

So as you can see, this treatment is cause dependent. If you have tinnitus, you need detail clinical examination and treatment. There is no over the counter drugs for this. I would suggest you to consult with the doctor and get evaluated.

Hope my answers have helped you.
Feel free to ask in case of any further queries.

Thanks.

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