Triptorelin (Decapeptyl SR or Gonapeptyl) for prostate cancer

Triptorelin is a type of hormone therapy . You pronounce it as trip-toe-reh-lin.

It is a treatment for prostate cancer.

Triptorelin is also used to treat breast cancer.

How does triptorelin work?

Prostate cancer depends on testosterone to grow. Testosterone is a type of sex hormone that your body naturally produces. Triptorelin blocks messages from the brain that normally tell the body to make testosterone. By blocking these messages, triptorelin reduces the amount of testosterone in the body. This can slow down or stop the growth of the cancer.

How do you have triptorelin?

You usually have triptorelin as an injection into a muscle (intramuscular), in your buttock or upper thigh.

If you're having a type called Gonapeptyl Depot, you can have the injection under the skin (subcutaneous injection) into your tummy (abdomen), thigh or top of your arm. You might have stinging or a dull ache for a short time after this type of injection, but they don't usually hurt much. The skin in the area may go red and itchy for a while.

How often do you have triptorelin?

You might have it triptorelin:

• once a month

• every 3 months

• every 6 months

You continue taking triptorelin for as long as the treatment is working and you are not experiencing too many side effects. 

Tests

You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.

What are the side effects of triptorelin?

Side effects can vary from person to person. They also depend on what other treatment you are having. 

When to contact your team

Your doctor, nurse, or pharmacist will go through the possible side effects. They will monitor you closely during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:

• you have severe side effects 

• your side effects aren’t getting any better

• your side effects are getting worse

We haven't listed all the side effects here. Talk to your healthcare team if you have any new symptoms that you think might be a side effect of your treatment.

Remember it is very unlikely that you will have all of these side effects, but you might have some of them at the same time.

Temporary side effects

You might have a temporary worsening of your symptoms after your first injection. They usually stop after 1 or 2 weeks. This is called tumour flare. So your doctor might give you another type of hormone drug to take at the same time to prevent the symptoms of tumour flare.

Symptoms of tumour flare include:

• increased pain or difficulty passing urine

• bone pain

• back pain

• blood in your urine

Common side effects

These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:

Low sex drive (libido)

Low testosterone levels can lower your interest in sex.

It can help to talk this through with your partner. You can still feel close to each other through cuddling and kissing. It may also help to talk to a counsellor or therapist. Your doctor or nurse can organise this for you.

Hot flushes and sweats

You may have hot flushes and sweat a lot. We have some tips for coping with hot flushes in men. This information also includes some of the possible treatments. Talk to your doctor if your hot flushes are hard to cope with. They might be able to prescribe some medicines to help.

Pain in different parts of the body

It is common to have back pain, joint pain or bone pain. Occasionally, you may get hand or foot pain, muscle aches, muscle pain and joint stiffness. Rarely you might have upper tummy (abdominal) pain or pain in the breasts or testicles. Let your healthcare team know so they can advise you on how to help reduce it.

Urine problems

You might feeling pain or discomfort when peeing (passing urine). You might need to get up in the night to pee.

Erection problems

You might have problems getting an erection (impotence). Talk to your doctor or nurse if you have this. There are treatments that can help, such as medicines, vacuum pumps and injections or pellets. Your doctor or nurse can refer you to a specialist in this area.

Abnormal sensations of the skin

You might have unusual skin sensations such as numbness, tingling, prickling or burning in your legs. It can feel like pins and needles.

Let your doctor or nurse know if you have this.

General weakness

You might feel weak and as though you lack energy. Various things can help you to cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.

Occasional side effects

These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include:

• an allergic reaction that can cause a rash, shortness of breath, redness or swelling of the face and dizziness - some allergic reactions can be life threatening, alert your nurse or doctor if notice any of these symptoms
• a change in mood or depression
• dizziness
• headaches
• high blood pressure
• dry mouth
• feeling sick
• redness, inflammation or tenderness at the injection site
• swelling due to a fluid build up in different parts of the body (oedema)
• pain in different parts of your body such as the pelvis , hands or feet. Or aches and pain in the muscles, bones, joints, ligaments, tendons or nerves (musculoskeletal system)
• weight gain
• problems with sleeping
• an increase in breast tissue
• feeling very tired and lack energy (fatigue)

Rare side effects

These side effects happen in fewer than 1 in 100 people (less than 1%). You might have one or more of them. They include:

• a severe allergic reaction
• decreased appetite or loss of appetite
• increased appetite
• weight loss
• a blockage in your artery, such as a blood clot (embolism)
• asthma getting worse
• hair loss or hair thinning
• testicles getting smaller
• liver changes that are usually mild and unlikely to cause symptoms. They usually go back to normal when treatment finishes. You have regular blood tests to check for any changes in the way your liver is working
• high level of platelets in the blood
• diabetes
• pain and swelling in the joints, usually the big toe (gout)
• high levels of fat in the blood (high cholesterol)
• difficulty sleeping (insomnia)
• problems with sight
• ringing in ears (tinnitus)
• the feeling of the room spinning or moving around you (vertigo)
• feeling your heartbeat in your chest (palpitations)
• shortness of breath
• nosebleeds
• constipation or loose poo (diarrhoea)
• being sick (vomiting)
• feeling very drowsy
• swelling caused by fluid build up in arms or legs (peripheral oedema)
• severe shivering (rigors)
• acne
• skin problems such as redness, itching or a rash
• muscle weakness and cramping
• kidney changes – you will have regular blood tests to check for this

Other side effects

There isn't enough information to work out how often these side effects might happen:

• weakened bones that are fragile and more likely to break (osteoporosis)
• an irregular heartbeat that needs treatment

Coping with side effects

We have more information about side effects and tips on how to cope with them.

What else do you need to know?

Other medicines, food and drink

Cancer drugs can interact with medicines, herbal products, and some food and drinks. We are unable to list all the possible interactions that may happen. An example is grapefruit or grapefruit juice which can increase the side effects of certain drugs.

Tell your healthcare team about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies. Also let them know about any other medical conditions or allergies you may have.

Contraception and pregnancy

This treatment might harm a baby developing in the womb. It is important not to get someone pregnant while you are having treatment and for a few months afterwards. Talk to your doctor or nurse about effective contraception before starting treatment. Let them know straight away if your partner becomes pregnant while you're having treatment.

Other conditions

If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.

More information about this treatment

For further information about this treatment and possible side effects go to the electronic Medicines Compendium (eMC) website. You can find the patient information leaflet on this website.

You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.