Side effects of antineoplastic drugs depend on the drug and the dosage used. These drugs are used in cancer chemotherapy for various reasons like preventing the cell growth, killing or shrinking the tumor or relieving symptoms. These drugs are of various categories and are often used in combinations.

Alkylating Agents

These drugs target the cellular DNA to kill them. Alkyl sulfonates, ethylenimines, nitrosoureas and triazines are some of the alkylating agents in chemotherapy that are generally used to treat breast cancer, lung cancer and ovarian cancer. However, alkylating agents increase the risk of developing leukemia in five to ten years after the initial treatment.

Antimetabolites

Antimetabolites disrupt the DNA and RNA development during the synthesis phase of cellular mitosis. Capecitabine, methotrexate and gemcitabine are some of the antimetabolites. These drugs are generally used for treating breast cancer, intestinal cancer, leukemia and ovarian cancer.

Anti-tumor Antibiotics

Antineoplastic drugs like anthracyclines, mitozantrone, actinomycin, bleomycin and mitomycin are some of the anti-tumor antibiotics that disrupt DNA of cancer cells. Anthracyclines are used to treat many cancers; however, high dosages of these drugs damage the heart permanently. The other antibiotics like bleomycin, etc are generally used to treat breast cancer, leukemia and prostate cancer.

Mitotic Inhibitors

Mitotic inhibitors are derived from plants and other natural compounds. They disrupt the cellular mitosis. Some of these drugs are epothilones, taxanes and vinca alkaloids. These are generally used to treat breast cancer, lung cancer and leukemia. However, excess use of mitotic inhibitors leads to nerve damage.

Topoisomerase Inhibitors

Topoisomerase inhibitors prevent topoisomerase enzymes from separating DNA strands during replication. Some of these drugs are etoposide, irinotecan and topotecan. They are generally used to treat gastrointestinal cancer, lung cancer and ovarian cancer. However, they tend to cause leukemia within two years after the initial treatment.

Targeted Therapy

Targeted chemotherapy is used to treat certain types of cancer. Trastuzumab used in this therapy is an antibody that affects the protein on cancerous cells. However, excess use of this drug could result in heart failure.

Antineoplastic drugs or chemotherapeutic agents tend to affect various organs of the body depending on the type of cancer, the dosage and the overall health of the patient. Some of the side effects according to the organs are:

Blood Problems

The bone marrow produces new blood cells to replace the old blood cells. Chemotherapy affects the bone marrow due to which this cell production is hampered. Hence, the blood counts fall which leads to certain disorders like anemia, bruising or low immunity depending on the type of cells that are low in the blood count.

Gastro Intestinal Tract

Some of the common gastrointestinal side effects are nausea, vomiting, mouth sores, diarrhea and constipation.

Hair Loss

Hair loss happens in two to three weeks after chemotherapy begins. However, this is temporary and hair grows back although with a slightly different color and texture.

Fatigue

Fatigue is obvious due to the extensive therapy and other factors like anemia, insomnia, depression and pain killer medications.

Nerve Problems

Chemotherapy causes numbness, pain and tingling in the hands and feet. This is called peripheral neuropathy or neuropathy in chemotherapy. It could be difficult to pick things in hands; there could be hearing loss, jaw pain or difficulty in balancing yourself.
Reproductive System

Sexual and reproductive side effects in men and women include a low libido. Men generally have erectile dysfunction while women could have vaginal and bladder infection, irregular menstruation and dryness in the vagina.

Skin and Nail

Skin becomes sensitive to the sun and it could become itchy, dry and red. The nails appear dry, yellowish and cracked.

Side effects of antineoplastic chemotherapy are bound to happen especially on those cells that have the fastest growth, as these drugs do not act selectively on cancer cells. However, there is research going on to develop new drugs, which have lesser side effects.