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Thyro-L Powder

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Thyro-L® Powder
Product Information
Thyro-L® Powder is used to treat low thyroid levels in horses, it is used when the thyroid gland does not produce enough thyroid hormone. 
Generic Name
Brand Names
Thyro-L®, Thyrozine Powder, Thyrosyn Powder®
Drug Class
Thyroid Hormone
Product Flavoring
Thyro-L® Powder is unflavored but has a slightly sweet palatable taste. 
*Contains lactose.
Product Description & Form
Thyro-L® Powder 1 lb Tub: gray powder. (NDC 11789-0048-10)
  • Helps correct conditions associated with hypothyroidism
  • Highly palatable taste
  • Each level teaspoon delivers approximately 12 mg of levothyroxine sodium
  • Tub contains 1 (5 ml) measuring scoop, 1 scoop is approximately 12 mg T-4
Active Ingredients
Levothyroxine sodium
Inactive Ingredients
Dibasic calcium phosphate dihydrate, microcrystalline cellulose, calcium silicate, alpha-tocopherol acetate, ethoxyquin, calcium carbonate, mineral oil, sodium chloride, lactose, corn oil, propylene glycol, butylated hydroxytoluene, citric acid monohydrate, butylated hydroxyanisole. 
Thyro-L® Powder should be given to your horse as directed by your veterinarian.
Missed Doses
Give the dose as soon as possible. If it is almost time for the next dose, skip the missed dose, and continue with the regular schedule. Do not give 2 doses at once.
Side Effects
When administered at the appropriate dose, there should not be any adverse effects. Notify your veterinarian if the following symptoms are noted: fast heart rate, excessive ingestion of food, excitability, nervousness, elevated respiratory rate.
Other side effects may occur. If you notice anything unusual, contact your veterinarian.
Drug & Food Interactions
The following drugs can potentially interact with levothyroxine: epinephrine, norepinephrine, warfarin, insulin, estrogens, digoxin, theophylline, and ketamine. Contact your veterinarian if your horse experiences any unusual reactions when different medications are given together.
Make sure to tell your veterinarian what other medication you are giving to your horse. Quite often your veterinarian may prescribe two different medications, and a drug interaction may be anticipated. In this case, your veterinarian may vary the dose and/or monitor your horse more closely. 
Allergic reactions to medications may occur. Be sure to inform VetSource and your veterinarian if your horse has any known drug sensitivities or allergies. If your horse displays symptoms of an allergic reaction, call your veterinarian immediately or go to a veterinary emergency clinic. Symptoms may include but are not limited to: swollen lips, tongue, face, airways; difficulty breathing; agitation; profuse salivation; widespread hives and itching.
Adverse Reactions
If you are concerned that your pet has experienced an adverse reaction to this medication, please contact the manufacturer Lloyd at 800-831-0004 or Vetsource customer service at 877-738-4443.
Store at 68°F to 77°F in controlled room temperature. Do not store above 86°F . Avoid excessive heat (104°F). Keep this medicine out of reach of children. Store in a childproof container. Store this medicine in a cool, dry place at room temperature. Store away from heat and direct sunlight. Do not store this medicine in the bathroom, near the kitchen sink or in damp places. The medicine may break down if exposed to heat or moisture.
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Nutritional Info