Objective: The aim of study was to compare vitamin B₁₂ levels of the patients who applied to internal medicine outpatient department for the first time with complaints of dizziness and the control group. The role of vitamin B₁₂ in patients with the complaint dizziness was investigated.

Materials and Methods: A hundred and sixty patients with the complaint of dizziness who applied to our internal medicine outpatient department for the first time and 120 patients who applied to Ordu University Faculty of Medicine Training and Research Hospital Internal Medicine clinic were included to the study. Age, gender, vitamin B12, folic acid, ferritin, hemoglobin, white blood cell (WBC) and mean corpuscular volume (MCV) values were recorded from the file records of the patients who applied to clinic. Patient data of both groups were compared statistically.

Results: The mean vitamin B₁₂ level of the patient group was 241.15±122.18 pg/mL and the mean vitamin B₁₂ level of the control group was 381.08±125.17 pg/mL. The mean vitamin B₁₂ level of the patient group was lower than the control group and this difference was statistically significant (P<0.001). Mean hemoglobin values, mean ferritin values and mean MCV values of the patient group were also significant in comparison with the control group (respectively P=0.01, P=0.004, P<0.001). However, there was no significant difference in mean folic acid levels between the groups (P=0.09).

Conclusion: Low vitamin B₁₂ level plays a role in the aetiology of dizziness. In patients who apply to the clinic with the complaint of dizziness level of vitamin B₁₂ should be measured and in case of deficiency adequate replacement would cause a decrease in complaints of the patients.