My sister has graves disease. She was on methinzole for 2 years. It was highly recommended for her to begin radioactive treatment. She started to feel ill when she came off the methinzole. She was off of it for 4-5 days and had to get a picture of her thyroid (to determine how much radioactive dye to minister to her). Her thyroid was originally 6X larger than normal, but then grew in size (throat) almost 9X larger. This dye will will remain in her system for approd. two months (to shrink the enlarged thyroid glands. However, everyone she talks to has never had the side effects that she still has (naseau, heart beating too fast, hot flashes, lack of energy, constant headaches, a feeling of her stomache being hollow. She has a new physician and her gut feeling is that there is something else wrong with her. Please help. My #: 631.667.4409. Thank you very much!