What can i do to help numbness in ms? at the moment i just have vague numbness in an arm and a very numb finger but i'm scared of it getting worse

Treatments??: You say you have ms, have had optic neuritis, and now numbness. Am perplexed, as you do not list any specific disease modifying therapy. Are you seeing a neurologist, are you on medication? If not, you should be. Is your numbness secondary to a peripheral nerve comorbidity, such as ulnar nerve issue? Has this been checked with emg? This requires management by an expert neurologist.