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Thyro-L Powder

THYRO-L Powder

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THYRO-L Powder

1 Lb - Jar (453.6 g)
10 Lbs - Bucket (4.536 kg) Free Shipping
SKU: 4182
Price: $27.95

  • Veterinarian Prescription (Rx) Required
  • Free Shipping on orders over $75
  • Levothyroxine Sodium Powder for Horses
RX required for this item.
Click here for our full Prescription Policy and Form

Levothyroxine sodium powder, USP for horses

Why Thyro-L?
  • the original levothyroxine powder supplement for predictable therapeutic results
  • manufactured under strict quality control guidelines
  • helps correct infertility
  • promotes normal shedding
  • reduces cutaneous swelling in neck and head areas
  • stimulates sweating in working horses
Thyro-L can be administered by mixing the daily dose in the concentrate or by top dressing on grain, preferably rolled or ground.

Each pound contains Levothyroxine Sodium USP...0.22% (1,000 mg)

Vet-A-Mix by Lloyd

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Levothyroxine sodium powder, USP for horses

Indications: For use in horses for correction of conditions associated with low circulating thyroid hormone (hypothyroidism).

Dosage: The suggested initial dose is 0.5 to 3.0 mg levothyroxine sodium (T-4) per 100 pounds body weight (1 to 6 mg per 100 kg) once per day or in divided doses. Response to the administration of Thyro-L should be evaluated clinically until an adequate maintenance dose is established. In most horses, this is usually in the range of 6 to 36 mg (1/2 to 3 level teaspoons) total daily dose of T-4. Serum T-3 and T-4 values can vary greatly among individual horses on thyroid supplementation. Dosages should be individualized and animals should be monitored daily for clinical signs of hyperthyroidism or hypersensitivity.

Administration: For oral dosing as directed by a veterinarian.

Warning: Use with caution in animals with clinically significant heart disease, hypertension or other complications for which a sharply increased metabolic rate might prove hazardous. Use in pregnant mares has not been evaluated.

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

Active Ingredient per pound (453.6 g):

Levothyroxine Sodium

0.22% (1,000 mg)

One level teaspoonful contains approximately 12 mg of T-4.

One level tablespoonful contains approximately 36 mg of T-4.

Teaspoon measure included.



Store at room temperature and protect from light. Avoid excessive heat (104°F).

LLOYD, Inc., Shenandoah, IA 51601 USA

Net Wt:

List No.


One Pound (453.6 g)



10 Pound



NAC No.: 10500292

We are unable to ship prescriptions into Arkansas, Louisiana, Georgia, Mississippi,
and North Carolina
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Located in Hastings, Nebraska, Heartland Veterinary Supply & Pharmacy started as a Veterinary Clinic in 1981, specializing in the health and wellness of the equine, canine and feline species. We have a licensed Veterinarian and Pharmacist on site, as well as a helpful team with the knowledge and products you need to keep your horse, dog or cat healthy and happy. The Heartland Staff is dedicated to fast, courteous service.

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