Busulfan can cause a severe decrease in the number of blood cells in your bone marrow. Tell your doctor and pharmacist about all the medications you are taking. If you take busulfan with other medications that may cause a low blood count, the side effects of the medications may be more severe. If you experience any of the following symptoms, call your doctor immediately: fever, sore throat, ongoing cough and congestion, or other signs of infection; unusual bleeding or bruising.

Keep all appointments with your doctor and the laboratory. Your doctor will order laboratory tests before, during and after your treatment to check your body’s response to busulfan to see if your blood cells are affected by this drug. Your doctor may need to change your dose or tell you to stop taking busulfan for a period of time to allow your blood count to return to normal if it has dropped too low. Follow your doctor’s directions carefully and ask your doctor if you do not know how much busulfan you should take.

Busulfan may increase the risk that you will develop other cancers. Talk to your doctor about the risks of taking busulfan.

Busulfan is used treat a certain type of chronic myelogenous leukemia (CML; a type of cancer of the white blood cells). Busulfan is in a class of medications called alkylating agents. It works by slowing or stopping the growth of cancer cells in your body.

Busulfan comes as a tablet to take by mouth once a day. The length of treatment depends on the types of drugs you are taking, how well your body responds to them, and the type of cancer you have. Take busulfan at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take busulfan exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Your doctor may adjust your dose of busulfan depending on your response to treatment and any side effects that you experience. Talk to your doctor about how you are feeling during your treatment. Do not stop taking busulfan without talking to your doctor.

Busulfan tablets are also used in combination with other drugs to destroy the bone marrow and cancer cells in preparation for a bone marrow transplant.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Before taking busulfan,

• tell your doctor and pharmacist if you are allergic to busulfan, any other medications, or any of the ingredients in busulfan tablets. Ask your pharmacist for a list of the ingredients.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: acetaminophen (Tylenol); certain chemotherapy medications such as bendamustine (Treanda), carmustine (BiCNU, Gliadel Wafer), cyclophosphamide (Cytoxan), ifosfamide (Ifex), lomustine (CeeNU), melphalan (Alkeran), procarbazine (Mutalane), temozolomide (Temodar), thioguanine; clozapine (Clozaril, FazaClo); cyclosporine (Sandimmune, Gengraf, Neoral); itraconazole (Sporanox); medications for mental illness and nausea; phenytoin (Dilantin); or meperidine (Demerol). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with busulfan, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
• tell your doctor if you have previously received radiation therapy or treatment with other chemotherapy medications or if you have or have ever had seizures or a head injury. Also tell your doctor if you have taken busulfan before, but your cancer did not respond to the medication.
• you should know that busulfan may interfere with the normal menstrual cycle (period) in women, may stop sperm production in men. However, you should not assume that you cannot get pregnant or that you cannot get someone else pregnant. Women who are pregnant or breast-feeding should tell their doctors before they begin taking this drug. You should not plan to have children while receiving chemotherapy or for a while after treatments. (Talk to your doctor for further details.) Use a reliable method of birth control to prevent pregnancy. If you become pregnant while taking busulfan, call your doctor immediately. Busulfan may harm the fetus.

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Busulfan may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• nausea
• diarrhea
• loss of appetite or weight
• constipation
• sores in the mouth and throat
• dry mouth
• headache
• difficulty falling asleep or staying asleep
• feeling unusually anxious or worried
• dizziness
• swelling of the face, arms, hands, feet, ankles or lower legs
• chest pain
• joint, muscle or back pain
• skin rash
• itching and dry skin
• darkened skin
• hair loss

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately:

• black, tarry stools
• red urine
• unusual tiredness or weakness
• difficulty breathing
• changes in vision
• vomiting
• stomach pain
• seizures

Busulfan may cause ovarian failure and may stop girls from reaching puberty. Talk to your doctor about the risk of infertility caused by busulfan. Talk to your doctor about the risks of receiving this medication.

Busulfan may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA’s Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can’t be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

• black, tarry stools
• red urine
• unusual bruising or bleeding
• unusual tiredness or weakness
• sore throat, cough, fever, or other signs of infection
• nausea
• vomiting
• diarrhea
• sores in the mouth and throat

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

• Myleran^®

• Busulphan