| Obligatory | Must not donate if: a) Under investigation. b) Malignant. c) Radioactive iodine administered in this pregnancy or the preceding six months. d) Less than 24 months from stopping treatment with anti-thyroid tablets. | 
| See if Relevant | Autoimmune disease Surgery | 
| Reason for Change | The reference in 'Discretionary' to treatment with thyroxine has been removed. A link to 'Autoimmune Disease' has been added. |