Bortezomib

Bortezomib is a prescription medication used to treat multiple myeloma (a cancer of the bone marrow) and mantle cell lymphoma (a cancer of the immune system).

Bortezomib is in a class of medicines called proteasome inhibitors. These medications work by inhibiting the function of proteasomes, cellular complexes required to break down damaged or unneeded proteins inside cells, including cancer cells. The buildup of proteins causes cells to die, potentially slowing the progression of cancer.

This medication comes in an injectable form to be given directly into a vein (IV) or just under the skin by a healthcare provider. It may be given once or twice a week.

Common side effects of bortezomib include weakness, upset stomach, vomiting, and diarrhea.

Bortezomib is a prescription medicine used to treat:

• multiple myeloma (a type of cancer of the bone marrow)
• mantle cell lymphoma (a fast-growing cancer that begins in the cells of the immune system)

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

Bortezomib may be found in some form under the following brand names:

• Velcade

Common bortezomib side effects include:

• weakness
• upset stomach
• diarrhea
• vomiting
• constipation
• numbness, tingling, or burning sensations of the hands or feet
• low platelet counts
• low desire to eat
• fever
• low red blood cell counts
• stomach, bone, arm, leg, back, and joint pain
• dizziness
• shingles (herpes zoster)

Tell your doctor about any side effect that is bothersome or that does not go away.

Bortezomib may cause side effects, some of which can be serious. See the "Bortezomib Precautions" section.

This is not a complete list of bortezomib side effects. Ask your doctor or pharmacist for more information.

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

• amiodarone (Cordarone, Pacerone)
• carbamazepine (Carbatrol, Tegretol)
• cimetidine (Tagamet)
• clarithromycin (Biaxin)
• clopidogrel (Plavix)
• clozapine (Clozaril, Fazaclo)
• erythromycin (E.E.S., E-Mycin, Erythrocin)
• indinavir (Crixivan)
• itraconazole (Sporanox)
• ketoconazole (Nizoral)
• nelfinavir (Viracept)
• phenobarbital (Luminal)
• phenytoin (Dilantin, Phenytek)
• rifampin (Rifadin, Rifamate, Rimactane)
• ritonavir (Norvir)
• saquinavir (Fortovase, Invirase)
• St. John's Wort

This is not a complete list of bortezomib drug interactions. Ask your doctor or pharmacist for more information.

Bortezomib can cause serious side effects, some of which can be life-threatening.

Bortezomib can cause heart problems, liver failure, lung problems, kidney disease (inluding kidney failure), as well as peripheral neuropathy (nerve damage that causes numbness, burning or pain in hands and feet). 

Bortezomib can increase risk for infections and bleeding problems by reducing white blood cell and platelet counts. Regular blood tests will be needed to monitor blood cell counts during bortezomib treatment. 

This medicine can cause low blood pressure (hypotension) which can cause dizziness, lightheadedness, and fainting as well as blurred vision. 

• Do not drive a car or operate heavy machinery until you know how bortezomib affects you.
• Bortezomib may cause dizziness, lightheadedness, and fainting when you get up too quickly from a lying position. Get out of bed slowly, resting your feet on the floor before standing up to avoid dizziness.
• Stay hydrated. During bortezomib therapy you may experience vomiting and/or diarrhea. Drink plenty of fluids to avoid dehydration which puts you at a higher risk for dizziness and fainting.

Tell your doctor right away if you experience dizziness, light headedness, or fainting spells.

Bortezomib has been reported to cause a rare, reversible, brain condition known as reversible posterior leukoencephalopathy syndrome (RPLS). Tell your doctor right away if you experience:

• seizures
• high blood pressure
• headache
• tiredness
• confusion
• vision problems

This medicine may cause blood glucose (sugar) levels to increase. If you have diabetes, you will need to check your blood glucose levels often.

Because bortezomib can quickly kill cancer cells, a condition known as tumor lysis syndrome may occur, especially if you have advanced cancer or many tumors. Tumor lysis syndrome occurs when dying cancer cells release large amounts of potassium, phosphate, and nucleic acids into the blood stream, leading to kidney problems. Your doctor will monitor your blood and urine and treat this condition if it occurs.

Bortezomib may harm the unborn baby if taken during pregnancy. See "Pregnant" section for more information. It is not known if bortezomib is excreted in human breast milk.

Contact your doctor if you experience:

• rash 
• shortness of breath
• cough
• swelling of the feet, ankles, or legs
• convulsion
• persistent headache
• reduced eyesight
• an increase in blood pressure
• blurred vision

Grapefruit and grapefruit juice may interact with bortezomib and lead to potentially dangerous effects. Discuss the use of grapefruit products with your doctor.

Before receiving bortezomib, tell your doctor if you are allergic to bortezomib or any other medicine.

Be sure to tell your doctor about all of your medical conditions including if you have:

• heart, kidney, or liver disease
• herpes
• diabetes
• high cholesterol
• low or high blood pressure
• a history of fainting
• peripheral neuropathy (numbness, pain, tingling, or burning feeling in the feet or hands)

Tell your doctor if you are pregnant or breastfeeding.

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements.

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

This medication falls into category D. It is advised to use effective contraceptive measures to prevent pregnancy during treatment with bortezomib. Report pregnancy to your doctor immediately. You hould not receive bortezomib while pregnant or breastfeeding. If you wish to restart breastfeeding after treatment, discuss the appropriate timing with your doctor.

Tell your doctor if you are breastfeeding or plan to breastfeed. Although it is not known if bortezomib is excreted in human breast milk, or if it will harm to a nursing baby, breastfeeding is not recommended during bortezomib treatment. If you plan to restart breastfeeding after bortezomib treatment, discuss this with your doctor.

Bortezomib is an injectable medication that is administered by healthcare provider in a medical setting. It may be given intravenously (into a vein) or subcutaneously (just under the skin), usually in the thigh or stomach.

Bortezomib is usually given once or twice a week. Doses are always at least 72 hours (three days) apart.

Your doctor may tell you to take other medicines while receiving bortezomib. Follow these instructions carefully.

The bortezomib dose you receive is based on your height and weight which is used to calculate your body surface area. It is usually injected 2 times a week for 2 weeks, followed by 10 days without an injection. Bortezomib may also be given once a week for 4 weeks followed by 13 days without an injection. Follow your doctor's instructions about your individual dosing schedule. It is important to keep all of your appointments to receive your bortezomib dose.

If side effects become intolerable, you may need to wait longer between doses, receive a lower dose, or permanently stop the medicine if potentially serious side effects occur.

If bortezomib is administered by a healthcare provider in a medical setting, it is unlikely that an overdose will occur. However, if overdose is suspected, seek emergency medical attention.