Brief Answer:
benign positional vertigo

Detailed Answer:
Hello and thank you for your question.
Most of the time when patients develop BPV, it is due to calcium deposits in the semicircular canals in the inner ear. We do not know why some patients develop these deposits. Sometimes this condition responds to repositioning of these deposits which can be done by a physician in the office. If your doctor has not been successful in this then perhaps an ENT physician could help you.
Symptoms in BPV are often provoked by sudden head movements and episodes often last less than one minute. If your vertigo is more persistent BPV may not be the correct diagnosis.
The statement below is from the online site UpToDate
"Medications are not useful for the brief episodes of vertigo associated with BPV, except when the frequency of spells is very high. However, vestibular suppressants can be used as premedication with liberatory maneuvers, and may help patients who would not otherwise tolerate these maneuvers because of discomfort and nausea. In a randomized trial, patients given betahistine (24 mg twice daily for one week) along with the Epley maneuver had reduced dizziness symptoms compared with those treated with the maneuver alone."
The Epley maneuver is one of the maneuvers that your doctor can do in the office so perhaps they were giving you the betahistine in preparation for doing this procedure in the office.
In very persistent cases of BPV surgical options could be explored with an ENT surgeon.
See the following site for patient information on BPV (also called BPPV)

http://www.uptodate.com/contents/vertigo-a-type-of-dizziness-the-basics?source=search_result&search=benign+positional+vertigo&selectedTitle=3~19

I hope you are feeling better soon,
Dr. Robinson

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