Plicamycin

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Plicamycin

Definition

Plicamycin is also known as mithramycin and Mithracin. The medicine kills cancer cells. It may be used to treat cancer of the testicles. In addition, it may be used as treatment for hypercalcemia . Hypercalcemia is a condition characterized by high levels of calcium in the blood.

Purpose

Plicamycin is a drug used to treat testicular cancer in patients who are not good candidates for either surgery or x-ray therapy.

Plicamycin is also used to treat hypercalcemia. Many patients with hypercalcemia also have elevated levels of calcium in the urine. As treatment for this condition, plicamycin may not be a doctor's first choice. The reason for this is that plicamycin may cause serious side effects. Newer medicines, known as bisphosphonates , can effectively resolve hypercalcemia and these have fewer side effects. However, some patients cannot tolerate bisphosphonates. These patients may be given plicamycin.

Description

Plicamycin interacts chemically with the DNA in cells and so interferes with the production of RNA. It lowers levels of calcium in the blood by affecting the formation of new bone cells and interfering with the activities of certain hormones.

Recommended dosage

For testicular cancer, some doctors give 25 micrograms per kilograms of body weight every two to four days to start. However, if the patient has kidney or liver problems, these doctors may give 12.5 micrograms per kilogram instead. Others administer 25 to 30 micrograms per kilograms of body weight every eight to ten days. Others may give as much as 50 micrograms per kilogram of body weight per dose for approximately eight doses every other day.

For high levels of calcium in the blood and urine, fifteen to twenty-five micrograms per kilogram of body weight may be given every day for three or four days. Following this, additional medication may be required approximately once a week.

Precautions

This medication is often not given to patients with problems with blood clotting or with the bone marrow. Plicamycin should not be given to pregnant women, nursing mothers, or children younger than fifteen years of age. The medicine should be used with caution in patients with liver or kidney problems. To lessen side effects to the digestive tract, the medicine may be administered over the course of four to six hours. Additional precautions should be followed to minimize the chances that the medicine will cause blistering.

Since people taking plicamycin are at increased risk of developing an infection and of having bleeding problems, they should avoid people who do have an infection. In addition, they should wash their hands before touching the inside of their mouth, their eyes, or their nose. Also, they should not take aspirin or over-the-counter preparations containing aspirin. In addition, they should attempt not to cause bleeding, for example when they brush and floss their teeth or when they shave.

Doctors should carefully monitor blood counts, liver function, and kidney function for patients given more than one dose of plicamycin.

Certain precautions should be followed by all patients. For example, plicamycin probably should not be taken by anyone who is living is a household with someone who has recently received oral polio vaccine, as there is a risk of transmission of the polio virus. The person receiving plicamycin should wear a face mask if she or he is going to be in close proximity to anyone who has recently received the oral polio vaccine for an extended period. In addition, vaccinations should not be given to anyone who is taking plicamycin or anyone who recently took plicamycin.

Side effects

The side effects of plicamycin include a tendency for abnormal bleeding. There may be low levels of calcium, potassium, and phosphorous in the blood, as well as other blood problems. The face may become flushed. Kidney or liver problems may develop. If bleeding does occur there may be damage to the surrounding skin.

Other side effects may include diarrhea , loss of appetite (anorexia ), nausea and vomiting , and soreness of the mouth. Muscle cramps and abdominal cramps may develop, although these are likely to disappear as the body gets used to the medication. Uncommon side effects include pain, soreness at the injection side, fever , weakness, headache, depressed mood, fatigue , and drowsiness.

The side effects of this medicine tend to increase as the dose of the medicine exceeds 30 micrograms per kilogram.

It is important to notify the doctor if any of the following symptoms of plicamycin overdose appear: vomiting of blood; yellow eyes or skin; bloody, or black, tarry stools; swelling of the face or redness of the face; skin rash; or the appearance of tiny red spots on the skin.

Bob Kirsch

KEY TERMS

Hypercalcemia

Hypercalcemia is a condition characterized by high levels of calcium in the blood.