Diagnosis of the causes of thyrotoxicosis (destruction or increased functional activity of the thyroid tissue in nodular and diffuse thyroid pathology) is a key point in determining the management of patients with this pathology. Scintigraphy is the method of choice in differential diagnosis of the causes of thyrotoxicosis assessing the functional state of the thyroid gland. According to variable medical interest, thyroid scintigraphy can be performed using 99mTc-pertechnetate or radioactive iodine isotopes (123I, 124I, 131I). For thyroid uptake evaluation used scintigraphy with 99mTc-pertechnetate radiopharmaceutical, which is not organificates and quickly excretes from thyroid tissue. In case of thyroid iodine pharmacokinetics investigation radiopharmaceuticals labeled by iodine isotopes (123I,131I, 124I) are used. The review includes original scintigrams, tables and diagrams. Article shows thyroid scintigraphy informativity analysis, evaluates the place and role of the thyroid scintigraphy examinations in modern diagnostic algorithms taking into account the history of the disease, laboratory tests, ultrasound (TIRADS) and result ofFNA (Bethesda). Additionally authors focused on existing clinical guidelines analysis. An optimized algorithm for the diagnosis and treatment of diffuse and/or nodular thyroid pathology associated with thyrotoxicosis is proposed.