Methimazole (Thyroid)
Brands: Tapazole, Felimazole
Methimazole treats hyperthyroidism in cats by reducing thyroid hormone production.
Used for
- Hyperthyroidism
How it is given
- Administration
- oral
- Frequency
- twice daily
- Duration
- often lifelong
- Storage
- Store in a cool, dry place away from direct sunlight
- Pregnancy safety
- caution
Always confirm the exact dose with your veterinarian before giving any medicine.
Typical dose ranges
cat
- Standard
- 2.5 to 5 mg every 12 hours
dog
- Large dogs
- Not typically used
- Small dogs
- Not typically used
- Medium dogs
- Not typically used
Ranges are reference only. Your vet sets the dose for your pet's weight and condition.
Active ingredients
- Methimazole
Side effects
Common
- Vomiting
- Loss of appetite
Rare
- Skin rashes
Severe
- Liver enzyme elevations
Do not use when
- Liver disease
- Blood abnormalities
Interacts with
- Anticoagulants
- Beta-blockers
Warnings
- Regular blood monitoring
- Avoid in liver disease
Methimazole (Thyroid) questions
What if I miss a dose?
Administer as soon as possible, but skip if near the next dose.
Can I stop giving Methimazole suddenly?
Consult your veterinarian before making any changes.
Are there alternatives to Methimazole?
Yes, surgical or radioactive iodine treatment may be options.
How long will my cat need to take Methimazole?
Often a lifelong treatment.
Is Methimazole safe for pregnant cats?
Use with caution; consult your vet.
Full drug detail
Overview
Methimazole is a medication commonly used to treat hyperthyroidism in cats. This condition involves an overproduction of thyroid hormones, leading to various health issues. Methimazole helps manage these symptoms by reducing hormone levels.
How It Works
Methimazole works by inhibiting the enzyme thyroid peroxidase, which is crucial for thyroid hormone synthesis. This reduces the production of T3 and T4 hormones, helping to stabilize the condition.
Uses & Indications
Primarily used in cats, Methimazole is indicated for:
- Hyperthyroidism
Dosage Guidelines
Dosage should always be determined by a veterinarian. Typical dosages are:
- Cats: 2.5 to 5 mg every 12 hours
Administration
Methimazole is administered orally, usually in tablet form.
Side Effects
Common
- Vomiting
- Loss of appetite
Rare
- Skin rashes
Severe
- Liver enzyme elevations (requires immediate veterinary attention)
Precautions & Warnings
- Methimazole should not be used in animals with liver disease or blood abnormalities.
- Regular monitoring of blood work is necessary.
Drug Interactions
- May interact with anticoagulants
- Potential interaction with beta-blockers
Storage
Store in a cool, dry place away from direct sunlight.
FAQ
- What if I miss a dose? Administer as soon as possible, but skip if it's near the next dose.
- Can I stop giving Methimazole suddenly? Consult your veterinarian before making any changes.
- Are there alternatives to Methimazole? Yes, surgical or radioactive iodine treatment may be options.
- How long will my cat need to take Methimazole? Often a lifelong treatment.
- Is Methimazole safe for pregnant cats? Use with caution; consult your vet.