Thyro-Tabs is intended for use in dogs for correction of conditions associated with low circulating thyroid hormone (hypothyroidism).
THYRO-TABS (levothyroxine sodium tablets, USP) contain synthetic crystalline L-3,3’,5,5’tetraiodothyronine sodium salt [levothyroxine (T4) sodium]. Synthetic T4 is chemically identical to that produced in the human thyroid gland. Each THYRO-TABS tablet contains the inactive ingredients microcrystalline cellulose, calcium phosphate dibasic dihydrate, povidone, sodium starch glycolate, magnesium stearate, and butylatedhydroxy toluene. T-4 measurements should be made at 30 day intervals to establish the proper maintenance dose during a therapeutic trial with Thyro-Tab. A critical assessment of improvement in or resolution of clinical signs should be made after 12 weeks of levothyroxine sodium therapy. Further confirmation of the diagnosis could include withdrawal of the levothyroxine sodium therapy. A recurrence of clinical signs following cessation of therapy further supports the diagnosis. Correct diagnosis of hypothyroidism is important, since such a diagnosis normally commits an animal to life-long supplemental L-thyroxine replacement therapy. The principal objective of levothyroxine sodium administration is to achieve and maintain normal metabolism in the patient by providing an exogenous supply of synthetic L-thyroxine in amounts sufficient to maintain levels of the hormone within the animal’s normal physiologic range. Animal adaptation may necessitate regular monitoring of serum T-4 concentrations during the first several months of treatment to establish proper maintenance doses.
The TSH Response Test may be used to provide a definitive diagnosis in dogs with borderline resting serum T-4 values. The TSH dose, post-dose sampling times, and interpretation of pre- and post-TSH injection responses depend somewhat on the reference laboratory used.