In the U.S.—

In Canada—

• Antineoplastic
• Immunosuppressant

Chlorambucil (klor-AM-byoo-sill) belongs to the group of medicines called alkylating agents. It is used to treat cancer of the blood and lymph system. It may also be used to treat other kinds of cancer, as determined by your doctor.

Chlorambucil interferes with the growth of cancer cells, which are eventually destroyed. Since the growth of normal body cells may also be affected by chlorambucil, other effects will also occur. Some of these may be serious and must be reported to your doctor. Other effects may not be serious but may cause concern. Some effects may not occur for months or years after the medicine is used.

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

Chlorambucil may also be used for other conditions as determined by your doctor.

Chlorambucil is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S. and Canada)

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

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to chlorambucil or other cancer medicines.

Pregnancy—This medicine may cause birth defects if either the male or female is taking it at the time of conception or if it is taken during pregnancy. In addition, many cancer medicines may cause sterility which could be permanent. Sterility has been reported with this medicine and the possibility should be kept in mind.

Be sure that you have discussed this with your doctor before taking this medicine. It is best to use some kind of birth control while you are taking chlorambucil. Tell your doctor right away if you think you have become pregnant while taking chlorambucil.

Breast-feeding—Because chlorambucil may cause serious side effects, breast-feeding is generally not recommended while you are taking it.

Children—In general, this medicine has not been shown to cause different side effects or problems in children than it does in adults. However, some children with nephrotic syndrome (a kidney disease) may be more likely to have convulsions (seizures).

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of chlorambucil in the elderly with use in other age groups.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking chlorambucil it is especially important that your health care professional know if you are taking any of the following:

• Amphotericin B by injection (e.g., Fungizone) or
• Antithyroid agents (medicine for overactive thyroid) 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 radiation or cancer medicines—Chlorambucil may increase the effects of these medicines or radiation therapy on the blood

• Azathioprine (e.g., Imuran) or
• Corticosteroids (cortisone-like medicine) or
• Cyclophosphamide (e.g., Cytoxan) or
• Cyclosporine (e.g., Sandimmune) or
• Cytarabine (e.g., Cytosar-U) or
• Mercaptopurine (e.g., Purinethol) or
• Muromonab-CD3 (monoclonal antibody) (e.g., Orthoclone OKT3) or
• Tacrolimus (e.g., Prograf)—There may be an increased risk of infection and development of cancer because chlorambucil decreases the body's ability to fight them

• Probenecid (e.g., Benemid) or
• Sulfinpyrazone (e.g., Anturane)—Chlorambucil may increase the amount of uric acid in the blood. Since these medicines are used to lower uric acid levels, they may not work as well in patients taking chlorambucil

• Chickenpox (including recent exposure) or
• Herpes zoster (shingles)—Risk of severe disease affecting other parts of the body

• Convulsions (seizures) (history of) or
• Head injury—Increased risk of seizures

• Gout or
• Kidney stones (history of)—Chlorambucil may increase levels of uric acid in the body, which can cause gout or kidney stones

• Bone marrow depression or
• Infection—Chlorambucil decreases your body's ability to fight infection
• Previous failure of chlorambucil therapy—Repeat treatment with chlorambucil not recommended

Take this medicine only as directed by your doctor. Do not take more or less of it, and do not take it more often than your doctor ordered. The exact amount of medicine you need has been carefully worked out. Taking too much may increase the chance of side effects, while taking too little may not improve your condition.

Chlorambucil is sometimes given together with certain other medicines. If you are using a combination of medicines, make sure that you take each one at the proper time and do not mix them. Ask your health care professional to help you plan a way to remember to take your medicines at the right times.

While you are using chlorambucil, your doctor may want you to drink extra fluids so that you will pass more urine. This will help prevent kidney problems and keep your kidneys working well.

This medicine sometimes causes nausea and vomiting. However, it is very important that you continue to use the medicine, even if you begin to feel ill. Do not stop using this medicine without first checking with your doctor. Ask your health care professional for ways to lessen these effects.

If you vomit shortly after taking a dose of chlorambucil, check with your doctor. You will be told whether to take the dose again or to wait until the next scheduled dose.

Dosing—

The dose of chlorambucil will be different for different patients. The dose that is used may depend on a number of things, including what the medicine is being used for, the patient's weight, and whether or not other medicines are also being taken. If you are taking chlorambucil at home, follow your doctor's orders or the directions on the label. If you have any questions about the proper dose of chlorambucil, ask your doctor.

Missed dose—

If you miss a dose of this medicine and your dosing schedule is:

• One dose a day—Take the missed dose as soon as possible. Then go back to your regular dosing schedule. However, if you do not remember the missed dose until the next day, do not take it at all. Instead, take your regularly scheduled dose. Do not double doses.
• More than one dose a day—Take the missed dose as soon as possible. Then go back to your regular dosing schedule. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store in the refrigerator.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

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

While you are being treated with chlorambucil, and after you stop treatment with it, do not have any immunizations (vaccinations) without your doctor's approval. Chlorambucil may lower your body's resistance and there is a chance you might get the infection the immunization is meant to prevent. In addition, other persons living in your household should not take oral polio vaccine since there is a chance they could pass the polio virus on to you. Also, avoid persons who have taken oral polio vaccine within the last several months. Do not get close to them, and do not stay in the same room with them for very long. If you cannot take these precautions, you should consider wearing a protective face mask that covers the nose and mouth.

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

• If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or 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 if you notice any unusual bleeding or bruising; black, tarry stools; blood in urine 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 your teeth and gums. Check with your medical doctor before having any dental work done.
• Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
• Be careful not to cut yourself when you are using sharp objects such as a safety razor or fingernail or toenail cutters.
• Avoid contact sports or other situations where bruising or injury could occur.

Along with its needed effects, a medicine may have some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Also, because of the way these medicines act on the body, there is a chance that they might cause other unwanted effects that may not occur until months or years after the medicine is used. These delayed effects may include certain types of cancer, such as leukemia. Discuss these possible effects with your doctor.

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

• More Common
  • Black, tarry stools;  blood in urine or stools;  cough or hoarseness, accompanied by fever or chills;  fever or chills;  lower back or side pain, accompanied by fever or chills;  painful or difficult urination, accompanied by fever or chills;  pinpoint red spots on skin;  unusual bleeding or bruising 
  
  

• Less common
  • Large, swollen hives;  itching;  skin rash;  sores in mouth and on lips  
  
  

• Rare
  • Cough;  blisters on skin;  muscle twitching or jerking;  shortness of breath 
  
  

Check with your doctor as soon as possible if any of the following side effects occur:

• Less common
  • Joint pain;  swelling of feet or lower legs 
  
  

• Rare
  • Agitation;  confusion;  convulsions (seizures);  hallucinations (seeing, hearing, or feeling things that are not there);  tremors;  trouble in walking;  weakness (severe) or paralysis;  yellow eyes or skin 
  
  

• Symptoms of overdose (in the order of frequency)
  • Black, tarry stools;  blood in urine or stools;  cough or hoarseness, accompanied by fever or chills;  fever or chills;  lower back or side pain, accompanied by fever or chills;  painful or difficult urination, accompanied by fever or chills;  pinpoint red spots on skin;  unusual bleeding or bruising;  agitation;  convulsions (seizures);  trouble in walking 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

• Less common
  • Changes in menstrual period;  itching of skin;  nausea and vomiting 
  
  

After you stop using chlorambucil, it may still produce some side effects that need attention. During this period of time, check with your doctor if you notice any of the following side effects:

• Black, tarry stools;  blood in urine or stools;  cough or hoarseness (may be accompanied by fever or chills);  fever or chills;  lower back or side pain, accompanied by fever or chills;  painful or difficult urination, accompanied by fever or chills ;  pinpoint red spots on skin;  shortness of breath;  unusual bleeding or bruising  

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

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in product labeling, chlorambucil is used in certain patients with the following medical conditions:

• Cancer of the ovaries
• Cancer of the lymph system that affects the skin
• Hairy cell leukemia (a cancer of the blood and bone marrow)
• Nephrotic syndrome (a kidney disease)
• Tumors in the uterus (womb)
• Waldenström's macroglobulinemia (a certain type of cancer of the blood)
• Histiocytosis X (a certain type of cancer found primarily in children)

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