
Benazepril HCl/MethimAZOLE is a compounded formulation containing Benazepril HCl, MethimAZOLE, prepared by Mixlab for veterinary use. Available by prescription.
A transdermal pen is a simple way to give your pet medicine through their skin—usually used for cats by applying gel to the inside of their ear.
Step-by-Step:
Important: Only apply where your vet has directed—usually hairless areas. Never apply over fur or broken skin. Keep other pets from licking the area until it’s dry.
This compounded formulation combines benazepril, an ACE inhibitor, with methimazole, an antithyroid agent — two different drug classes. In compounding practice, clinicians may consider a combination like this for a multi-targeted approach. Your veterinarian determines whether it is appropriate based on your animal's diagnostic findings.
This description reflects the general pharmacology of the active ingredient's drug class; your veterinarian determines whether this approach is appropriate for your animal.
Prescription only. Use only under the direction of a licensed veterinarian. This information is not a substitute for veterinary diagnosis, prescribing or monitoring. Compounded drugs are not approved by the FDA for safety or effectiveness.
Commonly observed effects of benazepril HCl/methimazole administration include lethargy, a decrease in appetite and localized digestive changes such as vomiting or loose stools. Because methimazole can influence the blood profile, your veterinarian will monitor for shifts in white blood cell counts and liver enzymes through periodic blood work. The benazepril component may occasionally lead to hypotension (low blood pressure) or significant weakness. Owners should watch for signs of persistent scratching around the face, yellowing of the skin or eyes and fainting episodes, contacting their veterinarian promptly if these occur.
This medication is typically used with extra caution or avoided in patients with known severe liver disease or pre-existing low blood pressure. It is also carefully evaluated in pregnant or lactating animals, as these active ingredients can influence fetal development and are excreted in milk. Before starting a protocol, ensure your veterinarian has a complete history of all other prescriptions and supplements your pet is receiving, as significant interactions can occur with other heart medications or non-steroidal anti-inflammatory medications (NSAIDs). Your veterinarian is the right person to provide guidance on the necessary duration of use and the most commonly considered monitoring schedule to ensure the management approach remains suitable for your pet's individual health status.
Yes. Benazepril HCl/methimazole is a combination prescription medication and can only be dispensed by a licensed pharmacy upon receipt of a valid authorization from a licensed veterinarian. Mixlab verifies all authorizations before any medication is prepared or shipped to your home.
Yes. Because this specific combination of an ACE inhibitor and an antithyroid agent is not available as a single commercial product, Mixlab specializes in compounding it into customized strengths and flavored dosage forms—such as oral liquids or transdermal gels—to suit your cat's specific needs. The decision to use a compounded formulation rests with the prescribing veterinarian.
Veterinarians discuss this combination for cats with the relevant hormonal condition that also require support for their heart or kidneys. By placing both medications in a single preparation, it may help address the number of separate administrations required, which can help maintain a consistent management protocol and reduce stress for the feline patient.
The most important observational signs to watch for include intense scratching at the face or neck, a sudden loss of appetite or a yellow tint to the gums and skin. If you notice these signs or if your cat appears unusually weak or faints, you should contact your veterinarian immediately for a clinical assessment.




