Radio-iodine ablation requires TSH stimulation, which was historically achieved by thyroid hormone withdrawal for 3 to 5 weeks. During this period, patients suffered from symptoms of hypothyroidism. The recombinant human TSH (rhTSH, Thyrogen®, Genzyme Therapeutics, Cambridge, USA) was approved in Europe in 2005 as an alternative stimulation procedure to withdrawal during ablation. It allows patients to remain euthyroid on thyroid hormone therapy (that needs not to be withdrawn). However, this a costly drug (800 € per patient), whose economic efficiency needs to be checked.