Triptorelin (Decapeptyl ® SR, Gonapeptyl Depot ®)
This information is about a hormonal therapy called triptorelin, which is used to treat prostate cancer. It describes triptorelin, how it is given and some of its possible side effects.
This information should ideally be read with our general information about prostate cancer.
Triptorelin is a type of hormonal therapy used to treat advanced prostate cancer.
Hormones are substances produced naturally in the body. They act as chemical messengers and help control the activity of cells and organs. Hormonal therapies interfere with the production or action of particular hormones.
Most prostate cancers need a supply 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. Triptorelin reduces the production of luteinising hormone, which leads to a reduction in testosterone levels. This may shrink or slow down the development of the cancer.
How triptorelin is given
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Triptorelin is given by injection into the muscle of the buttock (intramuscularly), or as an injection under the skin (subcutaneously). It can be given as a monthly injection, or as a longer-acting preparation every three or six months. It can be given by your GP or practice nurse at the surgery. If you are not able to visit the surgery, a district nurse can give you the injection at home.
You may find the injection slightly uncomfortable and may notice an area of redness or darker skin at the injection site afterwards. If you find the injection very uncomfortable, you can have a tiny amount of local anaesthetic to numb the area before the triptorelin is given.
When triptorelin is given
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Triptorelin is given to treat prostate cancer that has spread into the tissues around the prostate gland (locally-advanced cancer). It may also be used to control prostate cancer that has spread to other parts of the body (advanced prostate cancer).
Your doctor will discuss with you the length of treatment they feel is appropriate for your situation. Triptorelin may be given for as long as it is controlling the cancer. This may be for several months or years.
Each person's reaction to any medicine is different. Many people have very few side effects, while others may experience more. 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 side effects that are not listed here, discuss them with your doctor or nurse.
There may be a temporary increase in testosterone levels for the first few days of having triptorelin treatment. Some men may have an increase in symptoms, such as bone pain, or may have problems passing urine. Rarely, other problems may occur due to a temporary increase in the size of the tumour. This is known as tumour flare and is normal. It should improve in a few weeks. If you have any problems, let your doctor know.
Other types of hormonal therapy, such as cyproterone acetate (Cyprostat ®), flutamide (Drogenil ®) or bicalutamide (Casodex ®) may be given for the first few weeks of starting triptorelin to prevent tumour flare.
Hot flushes and sweating
These can be common, but many people find that hot flushes wear off after a period of time. Let your doctor know if hot flushes are causing you problems, as medicines can sometimes be prescribed to counteract them. There are a number of ways to help reduce hot flushes and sweats. Some men find it helps to cut down on tea, coffee, nicotine and alcohol.
Some people find that complementary therapies such as acupuncture help. Your GP may be able to give you details about having these on the NHS.
Loss of sex drive (libido) and erection difficulties (impotence) can occur. These often return to normal after stopping the drug. Some men may find that these problems carry on after treatment finishes. Talk to your doctor or nurse if these effects are a problem, as they can prescribe drugs to help.
You may find our section on sexuality and cancer helpful.
Breast tenderness or fullness
Men may sometimes notice slight breast swelling and tenderness, known as gynaecomastia. Your doctor can advise you about how this can be prevented or treated.
Feeling sick (nausea), being sick (vomiting) and diarrhoea
These side effects are rare, and usually mild and easily controlled. Let your doctor know if you feel sick, vomit or have diarrhoea, as medicines can be prescribed to help.
Bone thinning (osteoporosis)
You may be at greater risk of osteoporosis if you are taking triptorelin for longer periods of time. Your doctor can give you advice on how this can be monitored and treated. Let them know if you have any discomfort in your bones or joints.
We have more information on how you can keep your bones healthy.
Risk of heart disease and diabetes
There may be an increased risk of developing heart disease or diabetes when taking triptorelin. However, the benefits of hormonal treatment generally outweigh the possible risks. You can discuss the possible risks and benefits in your situation with your specialist.
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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Missing an injection
If you miss an injection by 2-3 days it shouldn’t make a great difference. But it's important to remember that the benefits of the injections are designed to last for four, 12 or 26 weeks, depending on which preparation you’re prescribed, so you should have them as regularly as possible.
Non-cancer admission to hospital
If you’re admitted to hospital for a reason not related to the cancer, it’s important to tell the doctors and nurses looking after you that you are having hormonal treatment. You should tell them the name of your cancer specialist so that they can ask for advice.
It’s a good idea to know who you should contact if you have any problems or troublesome side effects when you’re at home. Your doctor or nurse will give you details of who to contact for advice. This should include ‘out-of hours’ contact details if you need to call someone during the evening, overnight or at the weekend.
This section has been compiled using information from a number of reliable sources including:
British National Formulary. 63rd edition. 2012. British Medical Association and Royal Pharmaceutical Society of Great Britain.
Electronic Medicines Compendium (eMC). www.medicines.org.uk (accessed September 2012).
Sweetman, et al. Martindale: The Complete Drug Reference. 37th edition. 2011. Pharmaceutical Press.
Thanks to Kavita Kantilal, ePrescribing Pharmacist, Debbie Wright, Oncology Pharmacist, and the people affected by cancer who reviewed this information. Reviewing information is just one of the ways you can help when you join our Cancer Voices network.