Compared to people, pets experience fewer and less severe side-effects. The main reason for this is that we use lower doses of drugs thus causing less toxicities. Pets also do not “know” that they have cancer or that they are receiving chemotherapy. They thus do not suffer from known conditions found in people such as “anticipatory nausea and vomiting”.
The normal tissues that are most sensitive to chemotherapy are the intestinal lining, the bone marrow (which makes red and white blood cells) and hair follicles.
Most cases of intestinal toxicity are mild and usually resolve on their own or with medication given at home. Some cases may require hospitalisation with more specific treatment but this is very rare. Suppression of the bone marrow may cause a drop in the white blood cell count leading to increased susceptibility to infection. Severe cases require hospitalisation with intensive treatment, but in most cases the white blood cells are checked on a weekly basis or before any chemotherapy is administered so as to pre-empt any potential side-effects.
Hair loss (alopecia) is not a common side-effect in pets. Only hair that is continually growing, is affected by chemotherapy, so only certain breeds may be affected (poodles and certain terriers). Whiskers, especially in cats, often fall out with chemotherapy treatment, but re-grow once chemotherapy is stopped.
There are many different types of chemotherapy agents and each has a different likelihood of causing side effects. If your pet is treated with drugs known to cause certain side effects, we will prescribe medications to help prevent these complications. In addition we will give you instructions on what to do if a problem should arise. We seldom see severe side effects as described and with proper management, most animals recover uneventfully from chemotherapy. Please keep in mind that any animal can have an unexpected reaction to any medication.