Mechlorethamine

Key Terms: Anemia, Antidote, Chemotherapy, Deoxynucleic acid, Food and Drug Administration, Intravenous, Metastatic.

Definition

Mechlorethamine is a chemotherapy medicine used to treat cancer by destroying cancerous cells. Mechlorethamine is marketed as the brand name Mustargen. It is also commonly known as nitrogen mustard.

Purpose

Mechlorethamine is approved by the Food and Drug Administration (FDA) to treat Hodgkin's disease and non-Hodgkins' lymphomas. It is also approved for certain types of leukemia, malignant lymphomas, and lung cancer. Mechlorethamine has been used to relieve symptoms caused by a build up of cancerous fluid in the lungs, abdomen, and around the heart.

Description

Mechlorethamine is one of the first chemotherapy drugs discovered to have an effect on cancer cells. Clinical trials with this agent began in the 1940s. Mechlorethamine is a member of the group of chemotherapy drugs known as alkylating agents. Alkylating agents interfere with the genetic material (DNA) inside the cancer cells, more specifically through cross-linking DNA strands, and prevent them from further dividing and growing more cancer cells. Mechlorethamine is commonly combined with other chemotherapy agents to treat cancer.

Recommended Dosage

A mechlorethamine dose can be determined using a mathematical calculation that measures a person's body surface area (BSA). This number is dependent upon a patient's height and weight. The larger the person, the greater the body surface area. BSA is measured in the units known as square meter (m²). The body surface area is calculated and then multiplied by the drug dosage in milligrams per square meter (mg/m²). This calculates the actual dose a patient is to receive.

Mechlorethamine is a yellowish liquid that is injected directly into a vein over a period of one to five minutes. It can also be applied onto the skin as an ointment for certain conditions.

Mechlorethamine is combined with other chemotherapeutic drugs vincristine (oncovin), procarbazine, and prednisone for treatment of Hodgkin's disease. The dose of mechlorethamine used in this regimen is 6 mg per square meter on day 1 and day 8 of a treatment cycle. This regimen is referred to as MOPP, and was one the initial regimens that caused a breakthrough in the treatment of Hodgkin's disease.

Mechlorethamine can also be infused into certain compartments in the body where cancerous fluid has accumulated. The dose for this treatment is based on a patient's weight in kilograms (1 kilogram is 2.2 pounds). Mechlorethamine is given at a dose of 0.2 to 0.4 mg per kilogram of body weight, infused directly into the area where the fluid is building up.

Precautions

Patients should notify their doctors if they have had any previous allergic reactions to chemotherapy treatment or if they have received radiation therapy.

Blood counts should be monitored regularly while on mechlorethamine therapy. During a certain time period after receiving mechlorethamine, there may be an increased risk of getting infections. Caution should be taken to avoid unnecessary exposure to crowds and people with infections.

Patients who may be pregnant or are trying to become pregnant should tell their doctors before receiving mechlorethamine. Chemotherapy can cause men and women to become sterile, or unable to have children.

Patients should check with their doctors before receiving live virus vaccines while on chemotherapy.

Patients should increase their intake of fluids while on this medication.

Side Effects

One of the most common side effects from receiving mechlorethamine is nausea and vomiting. The nausea and vomiting can begin within one hour from receiving the drug. Patients will be given antiemetics before and after receiving mechlorethamine to help prevent or decrease this side effect.

A common side effect from taking mechlorethamine is low blood cell counts (myelosuppression). When the white blood cell count is lower than normal (neutropenia), patients are at an increased risk of developing fever and infections. The platelet blood count can also be decreased. Platelets are blood cells in the body that cause clots to form to stop bleeding. When the platelet count is low, patients are at an increased risk for bruising and bleeding. Low red blood cell counts (anemia), make people feel tired, dizzy, and lacking in energy.

Less common side effects from mechlorethamine include diarrhea, loss of appetite (anorexia), mouth sores, liver problems, metallic taste in the mouth, fever, ringing in the ears or hearing loss, and inflammation at the injection site. Allergic reactions have been reported, some of them severe anaphylactic reactions.

Damage to nerves and nervous system tissues is uncommon with mechlorethamine therapy. However, some reports do exist of nerve damage that has resulted in numbness and tingling in the hands and feet.

Mechlorethamine can cause skin reactions. When applied on top of the skin, the area can become red, swollen, brown colored, itchy, and have a burning sensation.

Hair loss (alopecia), irritation, and change of color of the vein where the drug was injected can occur. If the drug is not given directly into the vein, or is accidentally injected into surrounding areas of tissue, an antidote must be administered to that area as soon as possible. The area will become painful, gray-colored, and the tissue will begin to die. This is considered a severe reaction, and medical personnel must be notified immediately.

Interactions

Radiation therapy along with mechlorethamine administration can cause severe damage to the bone marrow.

—Nancy J. Beaulieu, R.Ph., B.C.O.P.