how does this medication work? what will it do for me?

panitumumab belongs to the group of cancer-fighting medications known as antineoplastics. it is a monoclonal antibody that recognizes and attaches to certain types of cancer cells. this may prevent cancer cells from growing and dividing. panitumumab is used in combination with other medications to treat a certain type of colorectal cancer that has spread to other parts of the body (metastatic colorectal cancer) and has not been treated with other medications. it is also used alone to treat metastatic colorectal cancer that has not responded to other specific anticancer medications.

this medication may be available under multiple brand names and/or in several different forms. any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. as well, some forms of this medication may not be used for all of the conditions discussed here.

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 being given this medication, speak to your doctor. do not stop using this medication without consulting your doctor.

do not give this medication to anyone else, even if they have the same symptoms as you do. it can be harmful for people to take this medication if their doctor has not prescribed it.

what form(s) does this medication come in?

100 mg/5 ml
each ml of sterile, colourless solution contains 20 mg of panitumumab. nonmedicinal ingredients: sodium acetate usp, sodium chloride usp, and water for injection usp. preservative-free.

400 mg/20 ml
each ml of sterile, colourless solution contains 20 mg of panitumumab. nonmedicinal ingredients: sodium acetate usp, sodium chloride usp, and water for injection usp. preservative-free.

how should i use this medication?

the usual recommended dose of panitumumab is 6 mg per kilogram of body weight given as an infusion into a vein every 2 weeks. if you experience certain side effects or do not tolerate this medication, your doctor may temporarily stop this medication, restart it at a lower dose, and then gradually increase the dose until the recommended dose is reached.

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 receiving the medication without consulting your doctor.

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 to receive this medication within 3 days before or 3 days after each scheduled dose (except if your dose is adjusted because of side effects). if you miss an appointment to receive panitumumab, contact your doctor as soon as possible to reschedule your appointment.

this medication is stored in the refrigerator and should be protected from light. do not shake this medication or allow it to freeze.

do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. ask your pharmacist how to dispose of medications that are no longer needed or have expired.

who should not take this medication?

do not take panitumumab if you:

  • are allergic to panitumumab or to any of the ingredients of the medication
  • have or have had swelling of the lungs (interstitial pneumonitis) or scarring of the lungs (pulmonary fibrosis)

what side effects are possible with this 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
  • diarrhea (mild and not associated with other symptoms)
  • fatigue
  • mouth sores or ulcers
  • nausea
  • 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:

  • cracked, dry or itchy skin
  • diarrhea (more than one day along with fever, decreased urination, dizziness, or a fast heartbeat)
  • eye problems (e.g., itchy, dry, irritated eyes; infected eyes; increased tear production; vision changes)
  • irritation, redness of swelling of tongue or lips
  • leg pain or swelling
  • nail infection (swelling and inflammation around the finger nails and toe nails)
  • painful swollen skin
  • peeling or red raised skin
  • signs of dehydration (e.g., decreased urine, dry skin, dry and sticky mouth, sleepiness, dizziness, headache, thirst, confusion)
  • signs of kidney problems (e.g., decreased urination, nausea, vomiting, swelling of the feet and ankles)
  • signs of low blood calcium levels (e.g., muscle spasms, tingling or numbness of the fingers and mouth, twitching, or memory loss)
  • signs of low potassium levels in the blood (e.g., weakness, fatigue, muscle cramps, irregular heartbeat)
  • symptoms of lung problems (e.g., difficulty breathing, shortness of breath, wheezing)
  • skin fissures
  • skin infection (warmth, swelling, redness)
  • symptoms of an infusion reaction (fever, chills, shortness of breath, swelling of the face, rash, dizziness, increased heart rate, sweating)
  • symptoms of low magnesium levels in the blood (severe weakness and fatigue)
  • skin rash

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

  • symptoms of a blood clot in the lung (severe shortness of breath, coughing up blood, sudden chest pain)
  • symptoms of an allergic reaction (difficulty breathing, sweating, swelling of the face or throat, hives)
  • 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

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.

are there any other precautions or warnings for 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.

allergic reactions: this medication can cause allergic reactions and side effects that are related to receiving the infusion. some of these reactions can be severe. if you experience shortness of breath, wheezing, fever, chills, lightheadedness, dizziness, or swelling of the face and throat, tell your doctor immediately or get immediate medical attention.

diarrhea: this medication can cause diarrhea that can lead to dehydration (loss of too much water from the body). if you experience severe diarrhea for more than a day, or if you have diarrhea along with fever, decreased urination, dizziness, or a fast heartbeat, contact your doctor immediately.

eyes: panitumumab may cause eye problems including irritated, itchy, or infected eyes. inflammation or the formation of ulcers on the front of the eye have been reported. contact lens use is a risk factor for this type of problem. if you experience any eye irritation or changes to your vision, contact your doctor as soon as possible.

fluid and electrolyte balance: panitumumab may cause the levels of electrolytes such as potassium, sodium, magnesium, chloride, and calcium in the blood to change while taking this medication. if you experience symptoms of fluid and electrolyte imbalance such as muscle pains or cramps; dry mouth; numb hands, feet, or lips; or racing heartbeat, contact your doctor as soon as possible. your doctor will do blood tests regularly to monitor the levels of these electrolytes in your blood while you are taking this medication.

infusion reactions: this medication can cause a hypersensitivity or infusion reaction. symptoms of this type of reaction generally appear during the infusion of the medication and may include flushing, chest pain, shortness of breath, and a dramatic drop in blood pressure. these reactions can cause death if a health care provider is not informed immediately. if you experience any of these symptoms, or notice them happening to someone, let your nurse or doctor know immediately.

kidney function: panitumumab can cause decreased kidney function or kidney failure, especially for people who are experiencing dehydration, which can occur with severe diarrhea. if you experience puffy hands, face or feet, high blood pressure, unusual muscle cramping, or darkened urine, this medication may be affecting how well your kidneys are working. if you notice any of these symptoms, contact your doctor as soon as possible.

the safety and effectiveness of using this medication have not been established for people with kidney problems. if you have decreased kidney function or kidney disease, 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: the safety and effectiveness of using this medication have not been established for people with liver problems. if you have liver disease or decreased 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. your doctor may want to test your liver function regularly with blood tests while you are taking this medication.

lung problems: panitumumab and similar medications can cause lung problems. if you experience difficulty breathing or shortness of breath while you are taking this medication, contact your doctor immediately.

if you have or have had interstitial pneumonitis (swelling of the lungs causing cough and difficulty breathing) or pulmonary fibrosis (scarring and thickening in the lungs with shortness of breath), 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.

skin reactions: this medication commonly causes skin reactions. some of these reactions can be severe. if you experience skin redness, itching, rash, peeling, cracks, dryness, or swelling and inflammation around the nails, contact your doctor. since sunlight may worsen skin reactions caused by this medication, people taking it should wear sunscreen and a hat, and limit sun exposure.

pregnancy: panitumumab should not be used during pregnancy. women who could become pregnant should use effective contraception while receiving this medication and for 6 months after stopping it. if you become pregnant while taking this medication, contact your doctor immediately.

breast-feeding: it is not known if panitumumab passes into breast milk. if you are taking this medication, you should not breast-feed during treatment and for 2 months after the last dose.

children: the safety and effectiveness of using this medication have not been established for children less than 18 years of age.

seniors: people over the age of 65 years may be more at risk of side effects from this medication.

what other drugs could interact with this medication?

there may be an interaction between panitumumab and any of the following:

  • other chemotherapy medications
  • methoxsalen
  • porfimer
  • verteporfin

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 this medication. 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.

all material copyright mediresource inc. 1996 – 2023. terms and conditions of use. the contents herein are for informational purposes only. always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. source: www.medbroadcast.com/drug/getdrug/vectibix