**7.1. Radioactive iodine uptake (RAIU)**

RAIU is not required in each and every case of Graves' disease, but it is useful in excluding thyrotoxicosis caused by thyroiditis, factitious thyrotoxicosis, and type II amiodarone induces thyrotoxicosis. RAIU is absolutely contraindicated in pregnancy. In Graves' disease RAIU is diffusely increased.
