55 yr old male, complaining of aches and pains, did bloodwork and revealed deficiency with vitamin d (25-hydrox) of 13 ng/ml. Doctor has prescribed one 50,000 iu tablet of calciferol a week for 8 weeks. My question is the risk of toxicity at such high doses and should I have calcium monitored at intervals during the eight weeks or just vit d tested at end of 8 wek period??