ExoticRx · exoticrx.com/drugs/radioactive-iodine-i-131
US brand names:I-131
Radioactive iodine concentrated by thyroid tissue. Beta radiation destroys hyperplastic/neoplastic thyroid cells while sparing normal tissue.
Gold standard for feline hyperthyroidism (95% cure rate with single dose). Requires licensed facility and isolation period (1-4 weeks). Hypothyroidism risk (<5%). No daily medication needed.
Species references:All Cat (Domestic) drugs
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A dog/cat sample is shown here. Cited dosing for all 1 species — reptiles, birds, pocket pets, livestock, and equine — is free on the per-species pages above. Pro adds the weight-based calculator for every species.
| Species | Route | Dose | Frequency | Evidence | Source |
|---|---|---|---|---|---|
| Cat (Domestic) | SC | See the cited source for the printed regimen | Single dose (variable mCi) | Strong | Peterson ME: Radioiodine treatment of hyperthyroidism, Clin Tech Small Anim Pract 21:34-39, 2006.; Peterson ME, Becker DV: Radioiodine treatment of 524 cats with hyperthyroidism, J Am Vet Med Assoc 207:1422-1428, 1995. — Verified against Withrow & MacEwen's Small Animal Clinical Oncology, 5th Ed, p.531 (2026-08-01). — LOCATOR CONVENTION 2026-08-07: the bare 'p.531' in this citation is the PDF index of the held scan, not the printed page. The PRINTED page is p.517; verified by finding the drug named there. If you are holding the book, turn to p.517. — SOURCE EDITION: Withrow and MacEwen's Small Animal Clinical Oncology — ISBN 9781437723625, https://openlibrary.org/isbn/9781437723625 |
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