Bortezomib belongs to the group of cancer-fighting medications known as antineoplastics. It works by killing cancer cells. Bortezomib is used to treat multiple myeloma (cancer of the bone marrow) in combination with other medications for people who have not previously been treated and to treat relapsed multiple myeloma. Bortezomib is also used to treat mantle cell lymphoma (a type of non-Hodgkins lymphoma) for people who have not previously been treated, are unsuitable for stem cell transplantation, and for people who have become resistant to other medications or who have experienced a relapse.

Treatment with bortezomib must be started and given under the supervision of a health care professional qualified and experienced in the use of antineoplastic (anti-cancer) medications.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are using this medication, speak to your doctor. Do not stop using this medication without consulting your doctor.

The recommended dose of bortezomib varies according to body size. It is injected into a vein (intravenously) or under the skin (subcutaneously), once or twice weekly, for varying periods of time, depending on the condition being treated. There should be a minimum of 72 hours between each dose of bortezomib.

Very careful handling of this medication is required. It is always given under the supervision of a doctor in a hospital or similar setting with access to sterile equipment for preparation.

It is important this medication be given exactly as recommended by your doctor. If you miss an appointment to receive bortezomib, contact your doctor as soon as possible to reschedule your appointment.

Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are using the medication without consulting your doctor.

This medication should be stored at room temperature protected from light, and kept out of the reach of children. After mixing, the solution can be stored for up to 8 hours at room temperature. Safely discard any remaining solution after the dose is prepared.

Do not use this medication if you are allergic to bortezomib, boron, or any ingredients of the medication.

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 this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. 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
• anxiety
• blurred vision
• decrease or loss of appetite
• diarrhea
• difficulty breathing
• dizziness
• flu-like symptoms (e.g., achiness, sore throat, fatigue, sudden lack of energy, fever)
• general feeling of being unwell
• headache
• heartburn
• joint pain or stiffness
• muscle pain, cramps, or stiffness
• nausea
• numbness, burning, or tingling sensations in the hands or feet
• rash, itching, hives, redness, pain at injection site with SC injections
• red cyst on the eyelid
• red, swollen eyelids
• shivering
• swelling of the hands, feet, ankles, or lower legs
• trouble sleeping
• unusual tiredness or weakness
• vomiting
• weight loss

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:

• changes in blood pressure
• confusion
• cough
• dizziness, lightheadedness, or fainting
• inability to urinate
• low blood pressure (e.g., dizziness or fainting)
• shortness of breath
• skin rash
• signs of anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
• signs of bleeding (e.g., bloody nose, blood in urine, coughing blood, bleeding gums, cuts that don't stop bleeding)
• signs of breathing problems (e.g., shortness of breath, troubled breathing, wheezing, or tightness in chest, fast or irregular breathing)
• signs of blood clots in very small blood vessels (e.g., bleeding, bruising, kidney damage)
• signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
• signs of heart problems (e.g., fast, irregular heartbeat or pulse, chest pain, difficulty breathing)
• signs of infection (symptoms may include fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
• symptoms of dehydration (excessive thirst, weakness, decreased urine production, dark urine)
• symptoms of increased blood pressure: (e.g., chest pain, blurred vision, dizziness, excessive tiredness, headache, stronger or faster heartbeat)
• symptoms of increased blood pressure in the lungs (e.g., shortness of breath, fatigue, dizziness or fainting, chest pain or pressure, swelling ankles and legs, bluish colour to lips and skin, fast and pounding heartbeat)
• symptoms of liver damage (yellowing of the skin or eyes, abdominal pain, nausea, dark urine, pale stool, itching, or fluid buildup in the abdomen)
• symptoms of shingles (e.g., headache; sensitivity to light; aching joints followed by an itchy, tingling, or painful skin rash)

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

• chest pain
• irregular or rapid heartbeat
• seizures
• severe abdominal pain
• signs of a severe skin reaction such as blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort
• symptoms of a blood stream infection (e.g., fever, increased heart rate, increased breathing, confusion)
• symptoms of nerve damage (e.g., dizziness when rising from a standing or lying position, diarrhea, constipation, fever, urinary problems, inappropriate amount of sweating, numbness, paralysis, changes in heart rate, or difficulty breathing, chewing or swallowing)
• symptoms of a severe allergic reaction (e.g., hives; difficulty breathing; swelling of the face, mouth, tongue, or throat)
• symptoms of a stroke (sudden numbness or weakness, especially on one side of the body; sudden confusion, difficulty speaking or understanding speech; sudden problems with coordination or balance; sudden vision problems in one or both eyes; sudden, severe headache with no other cause)
• symptoms of gastrointestinal (stomach or intestine) bleeding (such as blood in the stools; black, tarry stools; coughing or vomiting up of blood or material that looks like coffee grounds; abdominal pain; shortness of breath; and weakness or fatigue)

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 this medication.

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 this medication.

Amyloidosis: If you have amyloidosis (an abnormal build-up of protein in organs such as the liver, heart, spleen, kidneys), discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Anemia: Bortezomib 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.

Your doctor will do blood tests regularly to monitor the number of specific types of blood cells, including red blood cells, in your blood.

Blood clotting: This medication 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 of any signs that your blood is not clotting as quickly as usual. Such symptoms may include black and tarry stools, blood in the urine, easy bruising, cuts that won't stop bleeding, or any other unusual bleeding.

Bleeding may also occur in the brain, causing a stroke. If you develop signs and symptoms of a stroke (e.g., sudden difficulty speaking, difficulty walking, sudden dizziness, sudden and severe headache, sudden numbness or inability to move arms or legs, sudden confusion, sudden vision problems in one or both eyes), get immediate medical attention.

If you have a bleeding disorder, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Blood Sugar: People who use bortezomib and are also taking oral medications to control high blood sugar are at risk of experiencing changes in their blood sugar control (low blood sugar or high blood sugar). Your doctor may need to monitor your blood sugar levels more closely and adjust the dose of your antidiabetic medication(s).

Dizziness/blurred vision: Bortezomib may cause dizziness, fainting, tiredness, or blurred vision. If you experience these side effects, do not drive or operate dangerous machinery. Even if you don't experience these side effects, drive and use machinery with caution.

Heart conditions: This medication has been linked with the development of congestive heart failure and reduced heart function. If you have a heart condition (e.g., heart failure, inflammation around the heart, abnormal heart rhythm), or are at risk of developing a heart condition (e.g., have high blood pressure, high cholesterol, diabetes, or are obese), discuss with your doctor whether any special monitoring is needed.

Infection: As well as killing cancer cells, this medication can reduce the number of cells that fight infection in the body (white blood cells). If possible, avoid contact with people who have a contagious infection and tell your doctor if you begin to 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.

Kidney function: Multiple myeloma often causes increased levels of calcium in the blood and decreased kidney function, even kidney failure. If you have reduced kidney function, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Liver function: Bortezomib is broken down by the liver. Liver disease or reduced liver function may cause this medication to build up in the body, causing side effects. If you have reduced liver function, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

This medication may also cause a decrease in liver function. If you experience symptoms of liver problems such as fatigue, feeling unusually 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.

Low blood pressure: Bortezomib can cause low blood pressure, especially when standing from a sitting or lying position. If you have a history of fainting, are taking medications that can cause low blood pressure, or are dehydrated (not enough water in the body from diarrhea, vomiting, or not drinking enough fluids), discuss with your doctor whether any special monitoring is needed. If you experience lightheadedness, dizziness, or fainting during treatment with this medication, contact your doctor.

Lungs: Very rarely, this medication can cause serious lung and breathing problems. If you experience any new or worsening cough or shortness of breath while using this medication, contact your doctor immediately. You doctor will order a chest X-ray before you start using this medication to use as a baseline should you develop breathing problems.

Nerve and muscle problems: Bortezomib can cause nerve and muscle problems. If you have a history of any numbness, pain, burning, or tingling in your hands or feet (neuropathy), discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. If you develop symptoms of neuropathy while using bortezomib, contact your doctor.

Posterior Reversible Encephalopathy Syndrome: Very rarely, this medication can cause a reversible brain problem called PRES (posterior reversible encephalopathy syndrome). If you develop a seizure, headache, weakness, confusion, loss of vision, or other vision changes while using this medication, get immediate medical attention.

Progressive multifocal leukoencephalopathy (PML): Bortezomib has been rarely associated with an increased risk of a rare brain infection called progressive multifocal leukoencephalopathy (PML), which can lead to disability or death. Signs and symptoms of PML include progressive weakness on one side of the body; clumsiness of limbs; vision disturbances; changes in thinking, memory, and orientation; confusion; and personality changes. If you notice any of these symptoms, get immediate medical attention.

Seizures: There have been occasional reports of seizures occurring with bortezomib. If you experience a seizure, seek medical treatment immediately.

Shingles: Bortezomib has been linked to an increased number of flare-ups of shingles (herpes zoster reactivation). If you have had chickenpox or shingles in the past, this is a possible effect of the medication. Symptoms of shingles include patches of itching, painful skin which develop into a blistering rash after several days, and should be reported to your doctor as soon as possible.

Tumour Lysis Syndrome: Bortezomib, like many other cancer medications, causes many cancer cells to be suddenly killed when treatment is first started. This can overwhelm the body with waste products from the cells. As a result, the body may not be able to keep up with getting rid of all the waste. When this happens, you may experience nausea, shortness of breath, notice cloudy urine or joint pain. This is called tumour lysis syndrome. Your doctor may prescribe some medications to help your body get rid of the waste products. Make sure you understand how to use these medications and report any of these signs or symptoms to your doctor immediately.

Pregnancy: No studies have been conducted to determine the effect of bortezomib on an unborn baby if the medication is used during pregnancy. People should avoid becoming pregnant while taking bortezomib, and should use effective contraception during bortezomib treatment and for the 3 months following treatment. If you become pregnant while using this medication, contact your doctor immediately.

Breast-feeding: It is not known if bortezomib passes into breast milk. If you are breast-feeding and taking this medication, it may affect your baby. People should not breast-feed while taking bortezomib.

Children and adolescents: The safety and effectiveness of bortezomib have not been established for use by children and adolescents less than 18 years of age.

For a full list of interactions, use the Drug Interaction Checker available on the Drugs.com website.

If you are taking other 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.

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.