PENTOSTATIN (Systemic)

Some commonly used brand names are:

In the U.S.?

• Nipent

In Canada?

• Nipent

Other commonly used names are 2'-deoxycoformycin and 2'DCF.

Category

• Antineoplastic

Description

Pentostatin (PEN-toe-stat-in) belongs to the group of medicines calledantimetabolites. It is used to treat hairy cell leukemia.

Pentostatin interferes with the growth of cancer cells, which are eventuallydestroyed. Since the growth of normal body cells may also be affected by pentostatin,other effects will also occur. Some of these may be serious and must be reportedto your doctor. Other effects may not be serious but may cause concern. Someeffects may not occur for months or years after the medicine is used.

Before you begin treatment with pentostatin, you and your doctor shouldtalk about the good this medicine will do as well as the risks of using it.

Pentostatin is to be administered only by or under the immediate supervisionof your doctor. It is available in the following dosage form:

Parenteral
• Injection (U.S. and Canada)

Before Using This Medicine

In deciding to use a medicine,the risks of taking the medicine must be weighed against the good it willdo. This is a decision you and your doctor will make. For pentostatin, thefollowing should be considered:

Allergies?Tell your doctor if you have ever had any unusual orallergic reaction to pentostatin.

Pregnancy?There is a chance that this medicine may cause birthdefects if either the male or female is taking it at the time of conceptionor if it is taken during pregnancy. Pentostatin has been shown to cause birthdefects in rats and mice. In addition, many cancer medicines may cause sterilitywhich could be permanent. Although sterility has not been reported with thismedicine, it does occur in animals and the possibility should be kept in mind.

Be sure that you have discussed this with your doctor before taking thismedicine. It is best to use some kind of birth control while you are receivingpentostatin. Tell your doctor right away if you think you have become pregnantwhile receiving pentostatin.

Breast-feeding?It is not known whether pentostatin passes intobreast milk. However, because this medicine may cause serious side effects,breast-feeding is generally not recommended while you are receiving it.

Children?There is no specific information comparing use ofpentostatin in children with use in other age groups.

Older adults?Many medicines have not been studied specificallyin older people. Therefore, it may not be known whether they work exactlythe same way they do in younger adults. Although there is no specific informationcomparing use of pentostatin in the elderly with use in other adults, thismedicine is not expected to cause different side effects or problems in olderpeople than it does in younger adults.

Other medicines?Although certain medicines should not be usedtogether at all, in other cases two different medicines may be used togethereven if an interaction might occur. In these cases, your doctor may want tochange the dose, or other precautions may be necessary. When you are receivingpentostatin, it is especially important that your health care professionalknow if you are taking any of the following:

• Amphotericin B by injection (e.g., Fungizone) or
• Antithyroid agents (medicine for overactive thyroid) or
• Azathioprine (e.g., Imuran) or
• Chloramphenicol (e.g., Chloromycetin) or
• Colchicine or
• Flucytosine (e.g., Ancobon) or
• Ganciclovir (e.g., Cytovene) or
• Interferon (e.g., Intron A, Roferon-A) or
• Plicamycin (e.g., Mithracin) or
• Zidovudine (e.g., AZT, Retrovir) or
• If you have ever been treated with x-rays or cancer medicines?Pentostatinmay increase the effects of these medicines or radiation therapy on the blood

• Probenecid (e.g., Benemid) or
• Sulfinpyrazone (e.g., Anturane)?Pentostatin may raise the amountof uric acid in the blood. Since these medicines are used to lower uric acidlevels, they may not be as effective in patients receiving pentostatin

Other medical problems?The presence of other medicalproblems may affect the use of pentostatin. Make sure you tell your doctorif you have any other medical problems, especially:

• Chickenpox (including recent exposure) or
• Herpes zoster (shingles)?Risk of severe disease affecting otherparts of the body

• Gout (history of) or
• Kidney stones (history of)?Pentostatin may increase levelsof uric acid in the body, which can cause gout or kidney stones

• Infection?Pentostatin may decrease your body's ability to fightinfection

• Kidney disease?Effects of pentostatin may be increased becauseof slower removal from the body

Proper Use of This Medicine

This medicineoften causes nausea and vomiting. However, it is very important that you continueto receive the medicine even if you begin to feel ill. Ask your health careprofessional for ways to lessen these effects.

Dosing?The dose of pentostatin will be different fordifferent patients. The dose that is used may depend on a number of things,including what the medicine is being used for, the patient's size, and whetheror not other medicines are also being taken. If you arereceiving pentostatin at home, follow your doctor's orders or the directionson the label. If you have any questions about the proper dose of pentostatin,ask your doctor.

Precautions While Using This Medicine

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly and to check forunwanted effects.

While you are being treated with pentostatin, and after you stop treatmentwith it, do not have any immunizations (vaccinations)without your doctor's approval. Pentostatin may lower your body's resistanceand there is a chance you might get the infection the immunization is meantto prevent. In addition, other persons living in your household should nottake oral polio vaccine since there is a chance they could pass the poliovirus on to you. Also, avoid persons who have taken oral polio vaccine. Donot get close to them and do not stay in the same room with them for verylong. If you cannot take these precautions, you should consider wearing aprotective face mask that covers the nose and mouth.

Pentostatin can lower the number of white blood cells in your blood temporarily,increasing the chance of getting an infection. It can also lower the numberof platelets, which are necessary for proper blood clotting. If this occurs,there are certain precautions you can take, especially when your blood countis low, to reduce the risk of infection or bleeding:

• If you can, avoid people with infections. Checkwith your doctor immediately if you think you are getting an infectionor if you get a fever or chills, cough or hoarseness, lower back or side pain,or painful or difficult urination.
• Check with your doctor immediately ifyou notice any unusual bleeding or bruising; black, tarry stools; blood inurine or stools; or pinpoint red spots on your skin.
• Be careful when using a regular toothbrush, dental floss, or toothpick.Your medical doctor, dentist, or nurse may recommend other ways to clean yourteeth and gums. Check with your medical doctor before having any dental workdone.
• Do not touch your eyes or the inside of your nose unless you havejust washed your hands and have not touched anything else in the meantime.
• Be careful not to cut yourself when you are using sharp objects suchas a safety razor or fingernail or toenail cutters.
• Avoid contact sports or other situations where bruising or injurycould occur.

Side Effects of This Medicine

Along with its needed effects, a medicine may cause some unwanted effects.Some side effects will have signs or symptoms that you can see or feel. Yourdoctor may watch for others by doing certain tests.

Also, because of the way these medicines act on the body, there is a chancethat they might cause other unwanted effects that may not occur until monthsor years after the medicine is used. These delayed effects may include certaintypes of cancer. Discuss these possible effects with your doctor.

Check with your doctoror nurse immediately if any of the following side effects occur:

More common

Cough or hoarseness; fever or chills; lower back or side pain; painful or difficult urination

Less common

Black, tarry stools; blood in urineor stools; chest pain; pinpoint red spots on skin; unusual bleeding or bruising

Check with your health care professional as soon as possible if any ofthe following side effects occur:

More common

Pain; skin rash or itching (sudden); unusual tiredness

Less common

Anxiety or nervousness; changes in vision; confusion; cramps in lowerlegs; mental depression; nosebleed; numbness or tingling of hands or feet; shortness of breath; sleepiness; sore, red eyes; sores in mouth or on lips; stomach pain; swelling of feet or lower legs; troublein sleeping

This medicine may also cause the following side effects thatyour doctor will watch for:

More common

Anemia; liver problems; low platelet counts

Less common

Kidney problems

Other side effects may occurthat usually do not need medical attention. These side effects may go awayduring treatment as your body adjusts to the medicine. Also, your health careprofessional may be able to tell you about ways to prevent or reduce someof these side effects. Check with your health care professional if any ofthe following side effects continue or are bothersome or if you have any questionsabout them:

More common

Diarrhea; headache; loss of appetite; muscle pain; nausea and vomiting; skin rash

Less common

Back pain; bloating or gas; constipation; dry skin; general feeling of discomfort or illness; itching; joint pain; weakness; weight loss

Other side effects not listed above may also occur in some patients. Ifyou notice any other effects, check with your doctor.

Additional Information

Once a medicine has been approvedfor marketing for a certain use, experience may show that it is also usefulfor other medical problems. Although these uses are not included in productlabeling, pentostatin is used in certain patients with the following medicalconditions:

• Cancers of the blood
• Cancers of the lymph system (a part of the body's immune system),including a type that affects the skin

Other than the above information, there is no additional information relatingto proper use, precautions, or side effects for these uses.