Segmentation by type further refines market taxonomy into three isotopic sub‑categories: I‑131, I‑123, and I‑125. I‑131, the sole beta‑emitter, dominates the therapeutic niche, capturing roughly 45 % of total market revenue due to its high dose requirements for thyroid cancer and hyperthyroidism treatment. I‑123, a pure gamma emitter with a 13‑hour half‑life, serves the diagnostic sector, especially thyroid function tests and SPECT imaging, contributing about 35 % of market value. I‑125, characterized by low‑energy gamma emissions and a 60‑day half‑life, is employed in brachytherapy and certain prostate cancer protocols, as well as in radioimmunoassays, accounting for the remaining 20 % of sales. The relative share of each isotope reflects clinical adoption rates, regulatory pathways, and pricing structures, collectively defining the overall Iodine Radioisotope market size and growth trajectory.