Drugs Information Online
Drugs and diseases reference index

Drugs and diseases reference index

Drugs reference index «abarelix Intramuscular, Injection»

abarelix (Intramuscular route, Injection route)

a-ba-REL-ix, SOE-dee-um KLOR-ide

Intramuscular routeKit

Immediate-onset systemic allergic reactions, some resulting in hypotension and syncope, have occurred after administration of abarelix. These immediate-onset reactions have been reported to occur following any administration of abarelix , including after the initial dose. The cumulative risk of such a reaction increases with the duration of treatment. Following each injection of abarelix, patients should be observed for at least 30 minutes in the office and in the event of an allergic reaction, managed appropriately.

Abarelix is indicated for the palliative treatment of men with advanced symptomatic prostate cancer, in whom LHRH agonist therapy is not appropriate and who refuse surgical castration, and have one or more of the following: (1) risk of neurological compromise due to metastases, (2) ureteral or bladder outlet obstruction due to local encroachment or metastatic disease, or (3) severe bone pain from skeletal metastases persisting on narcotic analgesia.

The effectiveness of abarelix in suppressing serum testosterone to castrate levels decreases with continued dosing in some patients. Effectiveness beyond 12 months has not been established. Treatment failure can be detected by measuring serum total testosterone concentrations just prior to administration on Day 29 and every 8 weeks thereafter .

    • Only physicians who have enrolled in the Plenaxis™ PLUS Program (Plenaxis™ User Safety Program), based on their attestation of qualifications and acceptance of prescribing responsibilities, may prescribe Plenaxis™ .

Immediate-onset systemic allergic reactions, some resulting in hypotension and syncope, have occurred after administration of abarelix. These reactions can occur after any dose, and patients should be observed for at least 30 minutes following each injection and managed appropriately if an allergic reaction occurs. Measure serum total testosterone concentrations to assess effectiveness and detect treatment failure. Only physicians who have enrolled in the PLENAXIS(TM) PLUS Program may prescribe PLENAXIS(TM) .

Commonly used brand name(s):

In the U.S.

  • Plenaxis

Available Dosage Forms:

  • Powder for Suspension
  • Solution

Uses For abarelix

Abarelix is a type of medicine called a gonadotropin-releasing hormone (GnRH) antagonist that lowers the male hormone testosterone in your blood. Testosterone makes most prostate cancers grow. Other ways to treat your prostate cancer are taking other hormone medicines to lower testosterone or surgery to remove your testicles. Abarelix is used when these other ways to treat prostate cancer cannot be used or are refused.

Abarelix is to be given only under the supervision of your doctor. It is to be injected into your buttocks.

abarelix was available only with your doctor's prescription.

abarelix was withdrawn from the U.S. market in May 2005, and is available only to patients who are currently receiving the medicine.

Before Using abarelix

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For abarelix, the following should be considered:

It is very important that you read the Patient Information for abarelix before you start getting injections. You will need to sign the last page if you agree with treatment with abarelix. If you have any questions about this ask your doctor.


Tell your doctor if you have ever had any unusual or allergic reaction to abarelix or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Studies on abarelix have only been done in adult patients, and there is no specific information comparing the use of abarelix in children with other age groups. Abarelix is not for use in children.


abarelix has been tested and has not been shown to cause different side effects or problems in older people than it does in younger adults.


Pregnancy CategoryExplanation
All TrimestersXStudies in animals or pregnant women have demonstrated positive evidence of fetal abnormalities. This drug should not be used in women who are or may become pregnant because the risk clearly outweighs any possible benefit.

Breast Feeding


There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Sodium Chloride

Studies in women suggest that this medication poses minimal risk to the infant when used during breastfeeding.

Interactions with Medicines

Using abarelix with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Amiodarone
  • Quinidine
  • Sotalol

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of abarelix. Make sure you tell your doctor if you have any other medical problems, especially:

  • Osteoporosis or
  • QT prolongation (rare heart condition)—abarelix may make these conditions become worse.

Proper Use of abarelix

Abarelix is only prescribed by doctors who are part of Plenaxis PLUS Program (Plenaxis User Safety Program) that is run by the pharmaceutical (drug) company that makes the medicine.

Abarelix is given as an injection (shot) in your buttocks. Your doctor or nurse will give you the injection. It is important that you keep your appointment with your doctor's office when your injection is due. If you are unable to keep your appointment, contact your doctor's office to be rescheduled as soon as possible. It is very important that you follow the schedule that your doctor planned for your treatment.

You must always wait in your doctor's office for at least 30 minutes after getting each abarelix injection (shot). If a serious or life-threatening allergic reaction happens it is usually soon after getting an abarelix injection. Tell your doctor right away if you feel warm, faint or lightheaded or if you have chest tightness, shortness of breath, redness of your skin, or swelling of your face, eyelids, tongue, or throat. These could be signs of an allergic reaction.

Abarelix is only used for treating advanced symptomatic prostate cancer when a patient cannot have or refuses other treatments for prostate cancer


The dose of abarelix will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of abarelix. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For parenteral dosage form (injection):
    • For advanced prostate cancer:
      • Adults—100 milligrams (mg) in the muscle (buttock) on Day 1, 15, 29 (week 4), and every 4 weeks thereafter.

Precautions While Using abarelix

It is very important that your doctor check you at regular visits. Your doctor will also want to do regular blood tests about every 8 weeks to check your testosterone level to see if abarelix is working for you. If you weigh more than 225 pounds there may be a greater chance that abarelix may stop working. Your doctor may also want to do blood tests to check your liver function before and during treatment with abarelix.

abarelix may cause loss in bone mineral density with extended treatment. Loss in bone mineral density can lead to the thinning of bones (osteoporosis). If you have any questions about this ask your doctor.

abarelix can cause a change in heart rhythm called prolongation of the QTc interval. This condition may change the way your heart beats and can cause fainting and serious side effects in some patients. Contact your doctor right away if you have any of these symptoms or any questions about this.

abarelix Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Less common
  • Fainting or loss of consciousness
  • fast or irregular breathing
  • itching
  • skin rash
  • swelling of the eyes or eyelids
  • tightness in the chest and/or wheezing
  • trouble with breathing

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common
  • Back pain
  • bladder pain
  • breast enlargement
  • breast pain
  • bloating or swelling of the face, arms, hands, lower legs, or feet
  • bloody or cloudy urine
  • body aches or pain
  • burning while urinating
  • chills
  • cough
  • decrease in frequency of urination
  • decrease in urine volume
  • diarrhea
  • difficult, burning, or painful urination
  • difficulty having a bowel movement (stool)
  • difficulty in passing urine (dribbling)
  • dizziness
  • ear congestion
  • feeling of warmth
  • fever
  • frequent urge to urinate
  • headache
  • loss of voice
  • lower back or side pain
  • nasal congestion
  • nausea
  • nipple enlargement
  • pain
  • rapid weight gain
  • redness of the face, neck, arms, and occasionally, upper chest
  • runny nose
  • sneezing
  • sore throat
  • sweating
  • tingling of the hands or feet
  • trouble in holding or releasing urine
  • trouble with sleeping
  • unusual tiredness or weakness
  • unusual weight gain or loss

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

The information contained in the Thomson Healthcare (Micromedex) products as delivered by Drugs.com is intended as an educational aid only. It is not intended as medical advice for individual conditions or treatment. It is not a substitute for a medical exam, nor does it replace the need for services provided by medical professionals. Talk to your doctor, nurse or pharmacist before taking any prescription or over the counter drugs (including any herbal medicines or supplements) or following any treatment or regimen. Only your doctor, nurse, or pharmacist can provide you with advice on what is safe and effective for you.

The use of the Thomson Healthcare products is at your sole risk. These products are provided "AS IS" and "as available" for use, without warranties of any kind, either express or implied. Thomson Healthcare and Drugs.com make no representation or warranty as to the accuracy, reliability, timeliness, usefulness or completeness of any of the information contained in the products. Additionally, THOMSON HEALTHCARE MAKES NO REPRESENTATION OR WARRANTIES AS TO THE OPINIONS OR OTHER SERVICE OR DATA YOU MAY ACCESS, DOWNLOAD OR USE AS A RESULT OF USE OF THE THOMSON HEALTHCARE PRODUCTS. ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE OR USE ARE HEREBY EXCLUDED. Thomson Healthcare does not assume any responsibility or risk for your use of the Thomson Healthcare products.

Comment «abarelix Intramuscular, Injection»