Mitoxantrone for Dogs

In humans, doctors prescribe mitoxantrone to treat a variety of cancers, as well as multiple sclerosis. This same drug is commonly used as a single agent chemotherapy drug, or with another drug, to treat a variety of cancers in dogs. The drug is classed as an antineoplastic and works by interfering with the growth of cancer cells in the body. If your dog receives a diagnosis of cancer, your veterinarian will determine which drugs may be most effective, with mitoxantrone being one of the common options.

As the name suggests, single-agent chemotherapy is a single medication treatment. Mitoxantrone is one drug that is often effective without the need for additional chemotherapy agents, depending on the cancer. Treatments for many cancers tend to do best with combination chemotherapy treatments, but some may require only a single-agent chemotherapy drug. In some cases, owners are unable to afford combination therapy and single-agent therapy offers the best chance of treatment.

Mitoxantrone is commonly used to treat a variety of cancers. According to Pet Cancer Center, the main cancers mitoxantrone is used to treat include canine lymphoma and transitional cell carcinoma. In addition to these two, Specialty Veterinary Compounding Pharmacy states that mitoxantrone works to treat mammary adenocarcinoma, squamous cell carcinoma, renal adenocarcinoma, fibroid sarcoma, thyroid carcinoma and hemangiopericytoma.

In 1991, researchers looked at the efficacy of mitoxantrone as a single-agent chemotherapy treatment against various cancers in dogs. Their study included 126 dogs with various types of cancers. Of the 126 dogs treated, 29 achieved full or partial remission. The cancers treated in those cases included the cancers previously mentioned, as well as hepatocellular carcinoma, rectal carcinoma, chondrosarcoma, oral malignant melanoma, cutaneous malignant melanoma, myxosarcoma and mesothelioma.

While chemotherapy drugs work to damage or kill cancer cells, they are also toxic to other cells in the body, leading to various possible side effects. Common side effects associated with mitoxantrone include nausea, vomiting, diarrhea and dehydration. In addition to these symptoms, mitoxantrone affects bone marrow activity, resulting in low red and white blood cells, as well as platelets. Mitoxantrone is administered through injection and if it leaks out of the vein during administration, it can cause inflammation of the surrounding tissue. If this occurs, contact your veterinarian immediately.

Because mitoxantrone can cause tissue irritation, use caution when disposing of your dog’s urine or feces. A small amount of the drug passes into the urine and feces and contact can cause skin irritation, according to Banfield Pet Hospital. In addition, do not spray cleaning solutions directly onto soiled areas as this can cause the traces of mitoxantrone to become airborne.