ThyroKare Tablets

Levothyroxine Sodium Tablets, Usp

ThyroKare Tablets Caution

Federal law restricts this drug to use by or on the order of a licensed veterinarian.

Administration

For use only in dogs, under the care of a veterinarian.

Description

Each Levothyroxine Sodium Tablet provides synthetic crystalline levothyroxine sodium (L-thyroxine).

Action:

Levothyroxine sodium acts as does endogenous thyroxine, to stimulate metabolism, growth, development and differentiation of tissues. It increases the rate of energy exchange and increases the maturation rate of the epiphyses. Levothyroxine sodium is absorbed rapidly from the gastrointestinal tract after oral administration. Following absorption, the compound becomes bound to the serum alpha globulin fraction. For purposes of comparison 0.1 mg of levothyroxine sodium elicits a clinical response approximately equal to that produced by one grain (65 mg) of desiccated thyroid.

Indications:

Provides thyroid replacement therapy in all conditions of inadequate production of thyroid hormones. Hypothyroidism is the generalized metabolic disease resulting from deficiency of the thyroid hormones levothyroxine (T4) and liothyronine (T3). Levothyroxine sodium will provide levothyroxine (T4) as a substrate for the physiologic deiodination to liothyronine (T3). Administration of levothyroxine sodium alone will result in complete physiologic thyroid replacement.

Canine hypothyroidism is usually primary, i.e., due to atrophy of the thyroid gland. In the majority of cases the atrophy is associated with lymphocytic thyroiditis and in the remainder it is non-inflammatory and as of yet unknown etiology. Less than 10 percent of cases of hypothyroidism are secondary, i.e., due to deficiency of thyroid stimulating hormone (TSH). TSH deficiency may occur as a component of congenital hypopituitarism or as an acquired disorder in adult dogs, in which case it is invariably due to the growth of a pituitary tumor.

Hypothyroidism in the Dog:

Hypothyroidism usually occurs in middle-aged and older dogs although the condition will sometimes be seen in younger dogs of the larger breeds. Neutered animals of either sex are also frequently affected, regardless of age.

Contraindications:

Levothyroxine sodium therapy is contraindicated in thyrotoxicosis, acute myocardial infarction and uncorrected adrenal insufficiency. Use in pregnant bitches has not been evaluated.

Precautions:

The effects of levothyroxine sodium therapy are slow in being manifested. Overdosage of any thyroid drug may produce signs and symptoms of thyrotoxicosis including but not limited to polydipsia, polyuria, polyphagia, reduced heat tolerance and hyperactivity or personality changes. Administer with caution to animals with clinically significant heart disease, hypertension or other complications for which a sharply increased metabolic rate might prove hazardous.

Adverse Reactions:

There are no particular adverse reactions associated with L-thyroxine therapy at the recommended dosage levels. Overdosage will result in the signs of thyrotoxicosis listed above under precautions.

Dosage:

The initial recommended dose in 0.1 mg/10 lb (4.5 kg) body weight, twice daily. Dosage is then adjusted according to patient's response by monitoring T4 blood levels at time intervals of four weeks. The usual maintenance dose is 0.1 mg/10 lb (4.5 kg) once daily.

Administration:

L-thyroxine tablets may be administered orally or placed in the food.

Dosage forms available:

0.1 mg, 0.2 mg, 0.3 mg, 0.4 mg, 0.5 mg, 0.6 mg, 0.7 mg, and 0.8 mg tablets in bottles of 180 and 1000.

Storage:

Store at 20°-25°C (68°-77°F) with excursions between 15º-30°C (59°-86°F) and protect from light.

Keep Out Of Reach Of Children

NEOGEN Vet™

Manufactured for Neogen^® Corporation, Lexington, KY 40511 USA

For more information call: 859/254-1221

L784-1004

Nac No.