Hello ,

Thanks for posting your query.

A sensory disturbance like tingling numbness, weakness, of a limb along with vision disturbances and headache can be suggestive of a neurological problem (hemiparesthesia)mostly either a stroke or transient ischemic attack or due to any vascular lesion or hemorrhage in brain.
Though it can occurr in infections too especially viral , but the absence of any prodromal ilness makes it less likely .The other symptoms to look out for is inability or decreased capacity to move the affected limb , any vomiting, breathing difficulty, bowel bladder disturbances etc.
If he has any history of high blood pressure, or on any medications or he has started experiencing these symptoms suddenly in the day or there is worsened progression of symptoms it is advisable to take him to an Emergency room facility for a neurological evaluation, fundoscopy eye examination and if feasible an urgent Computed tomography or CT scan of brain to rule out any brain hemorrhage or thromboembolism causing a stroke or stroke like illness.
Meanwhile he should avoid any strenous activity (even straining at stools), preferably take
complete bed rest and adequate fluids.
If he has any difficulty in swallowing and breathing please avoid solid foods needing chewing till
your doctor has examined him to prevent any gagging or aspiration of food.
Please do not neglect the symptoms as they do warrant a physical examination by a doctor.In case of Transient ischemia the symptoms will soon resolve on their own but in future can cause more severe attacks or stroke if it is left undiagnosed and untreated.

Hope I have answered your query.
Regards

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