So, I have been on 5000 IU's of D3 1x/day for 4 weeks now, plus I spent a week in the Sonoran desert and while I did use sunblock, I got enough break through sun to get a nice tan without burning. I had my level rechecked this week and it has only gone from 12 to 18. Is there any danger in taking 2x5000IU D3 pills a day? Should I try it? I am frustrated by the slow rise and a bit concerned I won't get it up to where it need to be before I have to have surgery in August. Since I am having a cervical spine fusion, I feel like the vitamin D would be important to get up before trying to make new bone.