Felanorm (methimazole) Oral Solution for Cats

Felanorm (methimazole) Oral Solution by Virbac is indicated for the treatment of hyperthyroidism in cats. As the first FDA-approved oral solution for feline hyperthyroidism, Felanorm offers a smooth, stress-free alternative to traditional tablets, ideal for cats who resist pilling or require precise dose adjustments.

Felanorm contains the active ingredient methimazole, which works by inhibiting the synthesis of thyroid hormones (T4 and T3) within the thyroid gland. By blocking thyroid peroxidase activity, Felanorm helps restore normal thyroid function and supports long-term management of this common endocrine disorder.

The honey-flavored liquid is readily accepted by most cats and allows for more accurate dose without the stress and struggles of oral pills, potentially improving compliance and overall treatment outcomes.

• The starting dose of Felanorm Oral Solution is determined by the prescribing veterinarian based on the cat’s serum total T4 (TT4) levels and clinical presentation.
• The liquid formulation allows for precise, incremental dose adjustments to achieve optimal control of hyperthyroidism.
• Hematology, biochemistry, and TT4 should be evaluated prior to initiating therapy and monitored after 3 and 6 weeks of treatment.
• Once stabilized, bloodwork should be monitored every 3 months, with dose adjustments made as needed.
• Cats requiring higher daily doses should be monitored more frequently.

Contraindications

• Do not use in cats with known hypersensitivity to methimazole or carbimazole.
• Do not use in cats with primary liver disease or renal failure.
• Do not use in cats with autoimmune disease.
• Do not use in cats with hematological disorders (anemia, neutropenia, lymphopenia, thrombocytopenia) or coagulopathies.
• Do not use in pregnant or lactating queens. Methimazole has demonstrated teratogenic and embryotoxic effects in laboratory animals.

• Methimazole has anti-vitamin K activity and may induce bleeding tendencies.
• Not for use in humans. Keep out of reach of children.
• Wash hands after handling Felanorm™ or treated cats.
• Pregnant women, women who may become pregnant, and nursing mothers should avoid direct contact with the solution, litter, or bodily fluids of treated cats.
• In case of accidental ingestion or significant exposure, seek medical attention immediately.

• Use with caution in cats with renal dysfunction. Correction of hyperthyroidism may reduce glomerular filtration rate and reveal underlying kidney disease.
• Monitor closely for signs of illness such as fever, lethargy, lymphadenopathy, or anemia.
• If adverse signs occur, discontinue treatment and perform appropriate diagnostic testing.
• Drug interactions may occur with anticoagulants, phenobarbital, beta-adrenergic blocking agents, digitalis glycosides, theophylline, and benzimidazole anthelmintics.