See the link to prohibited items ebay policy
Private sellers are not allowed to sell medicines.
They may be approved by the American Drug Agency but that is not the UK
https://www.ebay.co.uk/help/policies/prohibited-restricted-items/prescription-overthecounter-drugs-p...
There are links to the Gov regulations too.
I suffer with tinnitus and there is an interesting report by the Tinnitus Association which cutting it short says,
Although independent evidence is limited, what there is does not show that the components of this supplement are effective for tinnitus and that there may be risks involved in taking this supplement. We would suggest you talk to your GP before taking any new medication or supplement.
“Dietary supplements should not be recommended to treat tinnitus.
