Degarelix (Firmagon ®)
This information is about a hormonal therapy called degarelix, which is also called Firmagon®. It is used to treat advanced prostate cancer. Throughout this information we refer to it by its more commonly used name, degarelix.
Degarelix is a hormone therapy drug that can be used to treat advanced prostate cancer.
Hormonal therapies interfere with the production or action of particular hormones. Hormones are substances produced naturally in the body. They act as chemical messengers and help control the activity of cells and organs.
What Degarelix looks like
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Degarelix is available as a white to off-white powder that is mixed with a clear, colourless solution. A doctor or nurse must mix the solution before it is injected.
Most prostate cancers need supplies of the hormone testosterone to grow. Testosterone is produced by the testes and the adrenal glands. Production of testosterone by the testes is stimulated by another hormone called luteinising hormone. This is produced by the pituitary gland, which is situated in the brain.
Degarelix blocks the production of luteinising hormone by the pituitary gland. This immediately reduces the testosterone level in the blood. The cancer cells then grow more slowly or stop growing altogether, and the cancer may shrink in size.
Degarelix is usually given as an injection by a nurse or a doctor. It is injected just under the skin (subcutaneously). It’s usually injected into the fatty tissue of the tummy (abdomen). A different area of your tummy will be used each time. The injection site should be an area away from the ribs where you won’t have pressure from a waistband or belt.
On your first day, you’ll have two injections of the drug. After this, you’ll have one injection once a month. This is known as a maintenance dose. Your doctor will monitor your testosterone levels during treatment.
Although degarelix is licensed and can be prescribed in the UK, it has not been approved for use by the National Institute for Health and Clinical Excellence (NICE). NICE currently gives advice on which new drugs or treatments should be available on the NHS. As a result, degarelix may not be widely available on the NHS. We can give you more information on what you can do if a treatment isn't available.
Degarelix can be given for as long as it controls the cancer. If it stops controlling the cancer, your doctor can discuss other treatment options with you.
Each person’s reaction to any medicine is different. Some people have very few side effects while others may experience more. The side effects described here won’t affect everyone who has degarelix.
We have outlined the most common side effects but haven’t included those that are rare and therefore unlikely to affect you. If you notice any effects that are not listed here, please discuss them with your doctor or nurse.
Hot flushes and sweating (including night sweats)
These can be quite common, but many men find that the hot flushes wear off after a period of time.
There are a number of ways to help reduce or control hot flushes and sweats. Some men find it helps to cut down on tea, coffee, nicotine and alcohol. Research shows that hormones called progestogens or some antidepressants may be helpful in controlling hot flushes. Your doctor or nurse can discuss this with you. Some men find complementary therapies helpful. Your GP may be able to give you details about having these on the NHS.
Pain and redness at injection site
You may have some pain and inflammation at the injection site. Let your doctor know if this becomes troublesome.
Chills, fever or flu-like symptoms after the injection
Speak to your doctor or specialist nurse if you experience any of these symptoms. They can advise you about how to deal with them.
Effect on liver function
Your doctor will take blood samples to test how well your liver is working. Degarelix can sometimes cause the amount of certain chemicals produced by the liver to change. Usually this is only mild and you can continue to take degarelix. Very occasionally, you may need to stop taking the drug.
Tell your doctor if you notice any yellowing of the skin or eyes. This is uncommon, but if it happens, your doctor will probably want to check your liver function. If your liver function has changed, the drug will be stopped and your liver function will return to normal.
Tiredness and fatigue
Some people can get very tired, especially at the start of treatment. It's important to get plenty of rest. If tiredness is making you feel sleepy, don’t drive or operate machinery.
You may notice that you gain weight, particularly around your waist. Eating a healthy diet and exercising regularly may help control your weight.
Feeling sick (nausea) or being sick (vomiting)
Your doctor can prescribe very effective anti-sickness (anti-emetic) drugs to prevent or greatly reduce nausea and vomiting. If the sickness isn’t controlled, or if it continues, tell your doctor; they can prescribe other anti-sickness drugs that may be more effective.
You may experience a loss of sex drive (libido) or erection difficulties (impotence). These side effects may continue for as long as you’re taking degarelix, but they should improve if you stop taking the drug. Let your doctor know if you have any of these side effects, as they can prescribe medication to help.
Nipple tenderness and/or some swelling of the breasts
You may notice slight breast swelling and tenderness (which is known as gynaecomastia). Your doctor can advise you about how this can be treated or prevented.
If you experience dizziness, let your doctor know and don’t drive or operate machinery.
Always let your doctor or nurse know about any side effects you have. There are usually ways in which they can be controlled or improved.
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Osteoporosis (bone thinning)
You may be at a higher risk of osteoporosis if you’re taking degarelix for long periods of time. Your doctor can give you advice on how it can be monitored, and you might be asked to take calcium and vitamin D supplements. Let them know if you have any discomfort in your bones or joints.
Heart rhythm problems (arrhythmia)
Degarelix may increase heart rhythm problems. It’s important to tell your doctors if you have or have ever had heart rhythm problems or if you’re taking any medicines for this condition.
Interaction with other medicines
Degarelix can affect how some other medicines work. If you’re taking medicines that are used to treat heart rhythm problems (such as procainamide, amiodarone and sotalol) or medicines that can affect heart rhythm (such as methadone, moxifloxacine and antipsychotics), let your doctor know before beginning treatment.
Degarelix can trigger diabetes or, if you’ve already been diagnosed, make it worse. You may have to measure your blood glucose more frequently if you have diabetes.
It’s not advisable to father a child while taking degarelix, as it may harm the developing baby. It is important to use effective contraception while taking this drug and for at least a few months afterwards. You can discuss this with your doctor
This section has been compiled using information from a number of reliable sources including: