A Vitamin D level of 20.8 ng/mL indicates a mild insufficiency, which is extremely common and very easy to correct, so please do not worry. Your prescribed medication contains Alfacalcidol, an active form of Vitamin D. Since that specific brand is unavailable, you can look for alternative generic Alfacalcidol capsules or standard Cholecalciferol (Vitamin D3) supplements on our platform. I highly recommend consulting your prescribing doctor or a pharmacist to help you select the exact strength and equivalent generic formulation that best suits your treatment plan.