Thanks for the query to H.C.M. Forum.
Vestibulo-cocchlear nerve ( 8th) is responsible for hearing and balance.
Slight impairment in this nerve may develops hearing loss
, tinnitus, imbalance.
Other reason may due to hypertension
as you are a patient of high blood pressure
,amlopidine. losartan all lower the blood pressure.
Consult an E N T / physician and their opinion will matter.
As far as concerned about use of betahistine
,it depends upon the strength of drug ( dose 16 mg or 48 mg ).
Mienier's disease or bppv will be assessed by consultant.