I was diagnosed with hyperparathyroidism. We were treating my low vitamin d levels and once my vitamin d levels went up a bit, my pth went down again. Still high but more normal. My calcium level stays right around 10. I think I have a parathyroid tumor but all the doctors blow me off because my levels are becoming more normal. We stopped supplementing the vitamin d once they became normal, and now my calcium is rising again and my vitamin d is in the toilet. PTH is still high. Can anyone point me in the direction of some good literature? most of my searches are not revealing any information about decreasing levels, only increasing levels.