ExoticRx · exoticrx.com/drugs/levothyroxine
US brand names:Soloxine, Thyro-Tabs
Levothyroxine is dosed at 0.02 mg/kg PO q12h in dogs, per Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.777 (2026-08-01).. Verify against current literature before clinical use.
Synthetic T4 (thyroxine) that is converted to active T3 in peripheral tissues. Restores normal metabolic rate, thermogenesis, and organ function.
Dose based on body weight, adjusted by monitoring serum T4 levels (4-6 hour post-pill sample). Give on empty stomach. Monitor for signs of thyrotoxicosis (tachycardia, panting, anxiety). Dogs primarily.
Species references:All Cat (Domestic) drugsAll Dog (Domestic) drugs
Each ExoticRx dose rule is graded by the strength of its primary evidence — see the editorial process.
A dog/cat sample is shown here. Cited dosing for all 2 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 |
|---|---|---|---|---|---|
| Dog (Domestic) | PO | 0.02 mg/kg | q12h | Strong | Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.777 (2026-08-01). |
| Cat (Domestic) | PO | 0.05–0.1 mg per cat | q24h | Moderate | Scott-Moncrieff JC. Chapter 3: Hypothyroidism. In: Canine and Feline Endocrinology. 4th ed. Elsevier Saunders; 2015.; Peterson ME, Carothers MA, Gamble DA, Rishniw M. Spontaneous primary hypothyroidism in 7 adult cats. J Vet Intern Med. 2018;32(6):1864-1873. doi:10.1111/jvim.15417 — Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.778 (2026-08-01). |
Upgrade to Pro or Student to unlock the full dose ranges and frequency for every species. The drug's mechanism, warnings, indications, and cited sources are free to read.
View PlansSource citations and evidence levels available on the live page. Reference only — verify against current literature before clinical use.