Cat · Felis catus · typical adult weight 2.50–7.00 kg
Radioactive Iodine I-131 is used in cats for Hyperthyroidism (curative). Routes documented in cats: SC. A typical adult cat weighs 2.50–7.00 kg. ExoticRx lists 1 cited dose rule for Radioactive Iodine I-131 in cats, drawn from published veterinary references. Verify against current literature before clinical use.
US trade names: I-131
| Route | Dose | Frequency | Duration | Indication | Evidence | Source |
|---|---|---|---|---|---|---|
| SC | See the cited source for the printed regimen | Single dose (variable mCi) | Single treatment | Hyperthyroidism (curative) | 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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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-specific contraindications and adverse-reaction reports for cats may differ from canine / feline reference data — consult the primary citations listed with each rule.
Radioactive Iodine I-131 dose range in cats, with cited source references: SC See the cited source for the printed regimen Single dose (variable mCi). Reference ranges from cited sources — verify against current literature before clinical use.
Documented routes for Radioactive Iodine I-131 in cats: SC.
Cited course lengths for Radioactive Iodine I-131 in cats include: Single treatment. Duration depends on the indication — match it to the specific dose rule in the table above.
Radioactive Iodine I-131 is indicated in cats for: Hyperthyroidism (curative).
These are general warnings for Radioactive Iodine I-131 across species; consult the cat dosing table above for species-specific guidance. 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.
Why a species-specific page? Radioactive Iodine I-131 pharmacokinetics differ across species: dose ranges, intervals, and route preferences are not interchangeable. Cross-extrapolation from canine doses is unsafe in cats — the rules above are the citations specific to this species, not generic recommendations.
Sourced from published veterinary references; awaiting credentialed clinical reviewer. See our editorial process. Reference only — not veterinary advice.