My mother is undergoing HCV treatment PegInt +RBV. She got RBV induced anemia so due to which EPO 40,000 IU are being given to her every week. Now her MCV is also increasing. Currently it's 106. Doctor suggested for B12 tablet (1.5 mg) and she has already been taking it for the last 2 months but still MCV is increasing every week. Any idea what can be the reason for that?