Many people are initially hesitant to use chemotherapy to treat their pet's cancer because they do not want to compromise their pet's quality of life. An owner may be concerned that treatment with chemotherapy will cause severe side effects in their pet and will make their pet feel poorly. While side effects are possible with chemotherapy and are described in detail below, the main goal of chemotherapy use in veterinary patients is different than it is in human patients. Our primary goal in using these drugs is to provide the pet with a good quality of life for as long as possible. We treat cancer as aggressively as we can but not at the expense of the pet's quality of life. If the pet starts to experience significant chemotherapy-related side effects, we alter our treatment plan. Fortunately, most dogs and cats tolerate chemotherapy much better than human patients.

Generally, dogs and cats that receive chemotherapy feel normal the day they are given the drug. Perhaps 3 to 5 days later, an owner might report that their pet does not feel 100%. But within 24 to 48 hours, the pet is back to his or her normal self until the cycle continues with the next dose of drug. After each dose of chemotherapy, we discuss with an owner whether or not the side effects seen in his or her pet would warrant a change in the pet's therapy. If everyone agrees that the pet's quality of life is good, and as long as there is evidence that the chemotherapy drug is working against the pet's cancer, we continue with the treatment.