St. John's wort is not a homeopathic remedy. It is an herbal remedy, and I don't see a specific indication here.
A remedy is not selected on the basis of the condition, but on the basis of your symptoms, your general symptoms, your modalities, and everything else about you.
First of all, you need to be checked out by a neurologist.
Secondly, homeopathy is a serious and difficult science and requires 3 to 6 hours of anslysis before the first remedy is given, and therefore you need a classical homeopath.
I can show you some of the main remedies that come up if you give me more information. Symptoms, what makes them better or worse, peculiar symptoms, how you react in various types of weather, time of year, time of day, how is your sleep, what are your biggest fears...and so on.
For a classical homeopath, you have good ones in the UK. http://www.homeopathy-soh.org/
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