Brief Answer:
supportive care

Detailed Answer:
Thank you for asking

I read your question and i understand your concern. Numbness on left side of scalp with no prior history of any neurological illness is likely a neuropathy mostly nutritional or age related neuropathy. This numbness should however be examined and correlated for nay nearby cause. Like pathology of inner ear or middle ear infection can lead to such numbness as well. Evaluation of ear functions test should be done. if he has some ringing in his ears then its more likely.

If there is any eruption around his forehead or its tender to touch then should be evaluated for neurological causes as well. His blood pressure is fine so vascular causes unlikely.

I would say just take some tylenol, if he drinks alcohol quit it and use vitamin rich in B 1 to B 12 and have balanced diet rich in proteins and vitamins and see if it helps. if the issue persists, visit your local hospital and let them run some tests to find out the possible cause. If he develops symptoms of paralysis or slurry speech or hemiparesis or numbness extends and involve entire arms and legs, then he should be immediately referred to hospital.

I hope it helps. Take good care of yourself and dont forget to close the discussion please.

Regards
Khan

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