Overview of Chemotherapy
There are many chemotherapy drugs available, as well as medications such as interferon and interleukin (called biological therapies) and monoclonal antibodies (such as Herceptin and Rituxan) that are used to treat cancer.
Chemotherapy may cause short term (acute), long term (chronic), and permanent side effects, some of which may be severe. In many cases, side effects of chemotherapy can be prevented or controlled.
In some cases, chemotherapy drugs cause an allergic or hypersensitivity reaction. These reactions, which are triggered by an immune system response, may occur immediately (e.g., type I or type II reaction), or within hours or days of chemotherapy (e.g., type III or type IV reaction).
Anaphylaxis is a severe reaction that requires immediate treatment and may cause shock, low blood pressure, and death. Symptoms of an allergic reaction include the following:
- Breathing difficulty
- Flushing (redness of the face and neck)
- Hives (urticaria; raised, itchy blotches)
- Swelling (e.g., of the lips, tongue, eyelids)
- Systemic reactions (e.g., liver and kidney disorders)
Interferon and interleukin-2 are commonly used biological agents. Interferon has been shown to improve survival in non-Hodgkins lymphoma patients, as well as in melanoma patients and renal cell cancer patients. It is also used in patients with hepatitis C. Interleukin-2 can be used to treat patients with renal cell cancer and patients with melanoma. During treatment, these agents, which are naturally made by the body, are delivered in higher doses than the body is capable of producing.
The major side effects associated with biological agents are constitutional, particularly fever and flu-like symptoms with associated body and muscle aches (arthralgias and myalgias). Other side effects include water retention and water leakage (often seen with interleukin), shortness of breath, cardiac arrhythmias (irregular heart rates), and skin rashes. In some cases, neurological changes (e.g., memory loss, depression, suicidal ideation ) may occur. As with side effects of chemotherapy, these effects are temporary and reverse with discontinuation of the medication.
Most side effects of this treatment are constitutional, such as fever, chills, muscle aches, and lack of energy.