THE RANGE BETWEEN THERAPEUTIC AND TOXIC DOSES IS NARROW.
Vitamin D Resistant Rickets:
12,000 to 500,000 USP Units daily.
Hypoparathyroidism:
50,000 to 200,000 USP Units daily concomitantly with calcium lactate 4 g, six times per day.
DOSAGE MUST BE INDIVIDUALIZED UNDER CLOSE MEDICAL SUPERVISION.
Calcium intake should be adequate. Blood calcium and phosphorus determinations must be made every 2 weeks or more frequently if necessary. X-rays of the bones should be taken every month until condition is corrected and stabilized.