Felanorm (methimazole) is a prescription oral solution indicated for the treatment of hyperthyroidism in cats. Hyperthyroidism occurs when the thyroid gland over-produces thyroid hormone and is a lifelong condition that requires treatment.
Who is Felanorm (methimazole) 5 mg/ml Oral Solution for Cats for?
Cats
Why use Felanorm (methimazole) 5 mg/ml Oral Solution for Cats?
Helps treat hyperthyroidism in cats. Felanorm reduces the production of thyroid hormone in cats. Easy to administer oral solution.
How does Felanorm (methimazole) 5 mg/ml Oral Solution for Cats work?
Methimazole is an antithyroid drug that acts by blocking the biosynthesis of thyroid hormone in vivo. The primary action is to inhibit binding of iodide to the enzyme thyroid peroxidase, thereby preventing the catalyzed iodination of thyroglobulin and T3 and T4 synthesis.
Norbrook
Methimazole
How is Felanorm (methimazole) 5 mg/ml Oral Solution for Cats sold?
Felanorm is available in 30 ml or 100 ml bottles with a 1 ml dosing syringe.
What are the side effects of Felanorm (methimazole) 5 mg/ml Oral Solution for Cats?
The most common adverse reactions include change in food consumption (increase or decrease), lethargy, vomiting, diarrhea/loose stool, skin lesions, and abnormal vocalization.
What special precautions are there?
Keep away from children and animals. Use of Felanorm in cats with renal dysfunction should be carefully evaluated. Reversal of hyperthyroidism may be associated with decreased glomerular filtration rate and a decline in renal function, unmasking the presence of underlying renal disease. Due to potentially serious adverse reactions such as hepatopathy, immune-mediated anemia, thrombocytopenia, and agranulocytosis, cats on methimazole therapy should be monitored closely for any sign of illness including anorexia, vomiting, head/facial pruritus or edema, depression/lethargy, weight loss, anemia, skin lesions, diarrhea, fever, or lymphadenopathy. If a cat becomes ill while on Felanorm, the drug should be stopped and appropriate hematological and biochemical testing should be done (see ANIMAL SAFETY and POST APPROVAL EXPERIENCE). Anticoagulants may be potentiated by the anti-vitamin K activity of Felanorm. Concurrent use of phenobarbital may reduce the clinical effectiveness of Felanorm. CONTRAINDICATIONS: Do not use in cats with hypersensitivity to methimazole, carbimazole or the excipient, polyethylene glycol. Do not use in cats with primary liver disease or renal failure. Do not use in cats with autoimmune disease. See ADVERSE REACTIONS. Do not use in cats with hematological disorders (such as anemia, neutropenia, lymphopenia, or thrombocytopenia) or coagulopathies. See ADVERSE REACTIONS. Do not use in pregnant or lactating queens. HUMAN WARNINGS: Not for use in humans. Keep out of reach of children. For use in cats only. Wear protective single use, impermeable (e.g., latex or nitrile) gloves when administering the solution. Wash hands with soap and water after administration to avoid exposure to drug. Wear protective gloves to prevent direct contact with litter, feces, urine, or vomit of treated cats, and the solution. Wash hands after contact with the litter of treated cats. Methimazole is a human teratogen and crosses the placenta concentrating in the fetal thyroid gland. There is also a high rate of transfer into breast milk. Pregnant women or women who may become pregnant, and nursing mothers should wear gloves when handling the solution, litter or bodily fluids of treated cats. Individuals with an endocrine disorder that could be impacted by methimazole should use similar precautions. Methimazole may cause vomiting, gastric distress, headache, fever, arthralgia, pruritus, and pancytopenia. In the event of accidental ingestion/overdose, seek medical advice immediately and show the product label to the physician.Avoid skin and oral exposure, including hand-to-mouth contact. Wash any spillages or splatter from the skin immediately. Do not eat, drink, smoke/vape, or use smokeless tobacco while handling the product or used litter. Felanorm may cause skin or eye irritation. Avoid eye contact, including hand-to-eye contact. In case of accidental eye contact, rinse eyes immediately with clean running water. If irritation develops, seek medical advice.
Contact your nearest emergency animal hospital.
How can I store Felanorm (methimazole) 5 mg/ml Oral Solution for Cats?
Store at controlled room temperature 25°C (77°F) with excursions between 15°-30°C (59°-86°F) permitted. Keep the container tightly closed.
Use as directed by your Veterinarian.
DOSAGE AND ADMINISTRATION:
Always include the Instructions for Preparing a Dose of Felanorm (methimazole) Oral Solution and the Information for Cat Owners with the prescription. The starting dose of Felanorm is 2.5 mg administered every 12 hours. Following 3 weeks of treatment, the dose should be titrated to effect based on individual serum total T4 (TT4) levels and clinical response. Dose adjustments should be made in 2.5 mg increments. The maximum total dosage is 20 mg per day divided, not to exceed 10 mg as a single administration.
