Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Busulfex (Busulfan). If you are concerned about side effects, discuss the risks and benefits of Busulfex (Busulfan) with your doctor.

The following side effects have been reported by at least 1% of people taking Busulfex (Busulfan). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• abdominal pain
• Constipation
• darkening of skin
• decreased sexual ability
• Diarrhea
• Dry Mouth
• fatigue
• hair loss
• headache
• increased skin pigmentation
• itching
• loss of appetite
• missed or irregular menstrual periods
• mouth sores
• muscle and joint aches
• nausea
• rash
• sleeping problems
• weight loss
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

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

• dizziness
• fast or irregular heartbeat
• lightheadedness
• lower back or side pain
• persistent congestion
• persistent cough with shortness of breath
• puffiness or swelling around the face
• signs of Anemia (low red blood cells; e.g., dizziness,  pale skin, unusual tiredness or weakness, shortness of breath)
• signs of clotting problems (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don’t stop bleeding)
• signs of Depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
• signs of kidney problems (e.g., increased urination at night, decreased urine production, blood in the urine, change of urine colour)
• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
• swelling of the fingers, hands, arms, lower legs, or feet
• symptoms of infection (symptoms may include Fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
• tingling in the lower legs, hands, or feet

Stop taking the medication and seek immediate medical attention if any of the following occur:

• bleeding in the stomach or digestive system (e.g., bloody, black, or  tarry stools, spitting up of blood, vomiting blood or material that looks like coffee grounds)
• blurred vision
• chest pain
• seizures
• signs of a serious allergic reaction (e.g., Hives; difficulty breathing or swallowing; or swelling of the face, lips, tongue, or throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Busulfex (Busulfan).

Each 10 mL vial contains 60 mg of Busulfex (Busulfan) at a concentration of 6 mg per mL for intravenous use. Nonmedicinal ingredients: dimethylacetaminde and polyethylene glycol 400, NF, in quantities of 3.333 mL and 6.667 mL, respectively.

Do not take Busulfex (Busulfan) if you:

• are allergic to Busulfex (Busulfan) or any ingredients of Busulfex (Busulfan)
• have a low platelet count
• have a low white blood cell count
• have not responded well to Busulfex (Busulfan) in the past

There may be an interaction between Busulfex (Busulfan) and any of the following:

• Acetaminophen
• amphotericin B
• Azathioprine
• "azole" antifungals (e.g., itraconazole, ketoconazole, Voriconazole)
• bacillus Calmette-Guérin (BCG)
• Clozapine
• Deferiprone
• Denosumab
• echinacea
• Fingolimod
• Leflunomide
• Methotrexate
• Metronidazole
• Natalizumab
• Nivolumab
• other cancer medications or medications that suppress the immune system
• Phenytoin
• Pimecrolimus
• Roflumilast
• Tacrolimus
• Tofacitinib
• Trastuzumab
• vaccines

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Busulfex (Busulfan). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use Busulfex (Busulfan).

Anemia: Busulfex (Busulfan) may cause low levels of red blood cells. If you experience symptoms of reduced red blood cell count (anemia) such as shortness of breath, feeling unusually tired, or pale skin, contact your doctor as soon as possible.

Blood clotting: Busulfex (Busulfan) can reduce the number of platelet cells in the blood. Platelets help the blood to clot, and a shortage could make you bleed more easily.

Tell your doctor about any signs that your blood is not clotting as quickly as usual. Symptoms include black and tarry stools, blood in the urine, easy bruising, or cuts that won't stop bleeding.

Fertility: Sterility may occur with the use of Busulfex (Busulfan). Talk to your doctor about options for preserving fertility for the future.

Infection: As well as killing cancer cells, Busulfex (Busulfan) can reduce the number of cells that fight infection in the body (white blood cells). If possible, avoid contact with people who have contagious infections. Tell your doctor immediately if you notice signs of an infection, such as fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness. Your doctor will do blood tests regularly to monitor the number of specific types of blood cells in your blood.

Liver: People taking Busulfex (Busulfan) may have changes in liver function that produce abnormal liver test results. It may also cause blockage of some of the small blood vessels in the liver. Your doctor will monitor you for this with blood tests. If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

Lung disease: Busulfex (Busulfan) may in rare cases cause a form of lung disease that develops after your treatment with Busulfex (Busulfan) has been is completed. Contact your doctor immediately if you develop a persistent cough, shortness of breath, or fever. Routine breathing tests may be required.

Other cancers: The use of Busulfex (Busulfan) may increase your risk of developing another type of cancer, such as leukemias and tumours. Discuss any concerns you may have with your doctor.

Seizures: High doses of Busulfex (Busulfan) can increase the risk of seizures. If you have a history of Epilepsy or medical conditions that increase the risk of seizures, discuss with your doctor how Busulfex (Busulfan) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Busulfex (Busulfan), and whether any special monitoring is needed.

Pregnancy: There is a possibility of birth defects if either the father or mother is taking Busulfex (Busulfan) at the time of conception, or if it is taken during pregnancy. Effective birth control should be practiced while using Busulfex (Busulfan) and should be continued for 6 months after treatment with Busulfex (Busulfan) is complete. If you become pregnant while taking Busulfex (Busulfan), talk to your doctor immediately.

Breast-feeding: It is not known if Busulfex (Busulfan) passes into breast milk. If you are a breast-feeding mother and are taking Busulfex (Busulfan), it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.