this is a common dosage for vitamin d when your blood levels show that you are deficient. this amount is available by prescription only (since it is much higher than any over the counter versions) so your body can absorb it and help maintain a consistent level. you should have a follow-up appointment with your physician for additional blood work to see what your levels are after taking the medication for a few weeks. if you are unsure of what a medication may be used for talk to your pharmacist; after all we are the medication experts.
my internist has me on 50 000 iu of vitamin d per week. would you know of any reason to prescribe this amount?