Clinical Research Directory

Inclusion Criteria: * Age 18 years or older * 2 or more distinct episodes of benign paroxysmal positional vertigo within a 12-month period on history * At least 1 episode diagnosed based on physical examination by trained study personnel, meeting the diagnostic criteria of the Bárány Society * Episodes separated in time, with a minimum of 1 week symptom-free between episodes * Serum evidence of Vitamin D deficiency, as evidenced by 25-hydroxy vitamin D level of \<75 nmol/L (\<30 ng/mL)48 * Subject able to provide informed consent to participate in the study Exclusion Criteria: Potential subjects will be excluded if they * have another identifiable cause of vertigo identified on history or physical examination * have a history of allergy or medically significant adverse reaction to vitamin D or calcium carbonate * have a chronic medical disorder which is a contraindication to vitamin D or calcium carbonate supplementation, including uncontrolled hyperparathyroidism, nephrolithiasis, or GI malabsorption disorders * are on loop diuretic agents or thiazides * have a contraindication to routine bloodwork for study purposes, including being hospitalized with a critical illness, cellulitis at blood draw sites, or presence of vascular grafts.