A hormone injection that lowers sex hormone levels
Triptorelin
A hormone injection that lowers the body's sex hormones, used in prostate cancer, endometriosis and early puberty.
What is Triptorelin?
Triptorelin is a hormone medicine known as a GnRH analogue, which works by lowering the body's production of sex hormones such as testosterone in men and oestrogen in women. It is used in several conditions: to slow prostate cancer that depends on testosterone, to ease endometriosis, and to treat children with early (precocious) puberty. It is given as an injection, often a longer-acting one every few weeks or months. When first started, it can briefly raise hormone levels before lowering them, so in prostate cancer another medicine is sometimes added at the start. The effects on hormones reverse after treatment stops.
Education and reference only. This is a plain-language guide to Triptorelin — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Triptorelin is a synthetic version of a natural hormone signal (gonadotrophin-releasing hormone) that the brain uses to control the production of sex hormones. Used as a medicine, it ultimately switches down this signal so the body makes much less testosterone in men or oestrogen in women. This makes it useful in prostate cancer that grows in response to testosterone, in endometriosis where oestrogen drives the condition, and in children whose puberty starts far too early. It is given by injection, usually as a long-acting (depot) form that releases slowly over weeks or months, under specialist care.
How it works
Normally the brain releases its hormone signal in pulses, which tells the body to make sex hormones. Triptorelin floods the system steadily rather than in pulses, which after an initial surge causes the body to switch off this pathway, so testosterone or oestrogen drops to very low levels. In prostate cancer, low testosterone slows cancer that depends on it. In endometriosis, low oestrogen quietens the tissue that causes pain. In early puberty, lowering sex hormones pauses the changes until a more appropriate age. Because there is a brief surge first, a cover medicine is sometimes used at the start in prostate cancer to prevent a temporary flare.
Company & origin
Originated / developed by: Ipsen.
A specialist hormone medicine used in the UK to lower sex hormones in prostate cancer, endometriosis and early (precocious) puberty, given by injection.
Practical use
How to take Triptorelin
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given as an injection by a healthcare professional, often a long-acting form every few weeks or months, so attend your appointments on time.
- In prostate cancer, take any cover tablet you are given around the start to prevent a temporary flare.
- Expect symptoms linked to lower sex hormones, such as hot flushes, and tell your team if they are troublesome.
- Do not miss or delay injections, as a gap can let hormone levels rise again.
- Discuss bone health with your team if you are having longer treatment, as low sex hormones can weaken bones.
Weighing it up
Advantages & disadvantages of Triptorelin
Advantages
- An effective way to lower sex hormones for prostate cancer, endometriosis and early puberty.
- Available as long-acting injections given only every few weeks or months.
- Its hormonal effects usually reverse after treatment is stopped.
Disadvantages
- Causes a brief surge in hormones at the start, which may need a cover medicine in prostate cancer.
- Lowering sex hormones causes symptoms such as hot flushes, tiredness and reduced sex drive.
- Longer use can weaken bones, so treatment length and bone protection need attention.
Practical use
Good to know
The most important thing to understand is the initial surge, sometimes called a flare: when treatment starts, hormone levels briefly rise before falling, so in prostate cancer a tablet (an anti-androgen) is often given around the start to cover this. Once hormones are lowered, the effects are like a sharp drop in sex hormones, so men may notice hot flushes, tiredness and reduced sex drive, while women may have menopause-like symptoms such as hot flushes, mood changes and, with longer use, effects on bone strength. For this reason, longer courses in women are often limited or given with add-back hormone treatment to protect the bones. In children, treatment is paused at an appropriate age and puberty then resumes. Most of these hormonal effects reverse after treatment stops.
Who should not take it / use with caution
- People who have had a serious allergic reaction to triptorelin or similar medicines should not use it.
- It is not used in pregnancy or breastfeeding, and pregnancy must be excluded before starting in women who could become pregnant.
- It is used with caution in people at risk of weakened bones, and the situation is judged carefully by a specialist.
Monitoring
- Checking how well the condition responds, such as PSA blood tests in prostate cancer.
- Watching for and managing symptoms of low sex hormones.
- Reviewing bone health with longer treatment, sometimes with bone density scans.
Side effects
- Hot flushes, sweating, tiredness and reduced sex drive from the lower sex hormones.
- In women, menopause-like symptoms such as mood changes, vaginal dryness and, with longer use, bone thinning.
- Mood changes, headaches or reactions at the injection site in some people.
- A temporary flare of symptoms at the start, which is why a cover medicine may be used in prostate cancer.
Key interactions
- Tell your team about all your medicines, including those that affect bones or hormones.
- Medicines that affect the heart's rhythm may need review, as hormone changes can have effects on the heart.
- In prostate cancer, an anti-androgen tablet is sometimes used deliberately alongside it at the start.
Available as: An injection, usually a long-acting (depot) form given every few weeks or months.
Answers
Triptorelin: frequently asked questions
What is triptorelin used for?
It lowers the body's sex hormones and is used in prostate cancer, endometriosis and early (precocious) puberty in children.
Why might my symptoms flare at the start?
When treatment begins, hormone levels briefly rise before falling, so in prostate cancer a cover tablet is often given around the start to prevent a temporary flare.
How is it given?
It is given as an injection by a healthcare professional, usually a long-acting form every few weeks or months, so keeping appointments matters.
Will the effects wear off?
Yes, the hormonal effects usually reverse after treatment is stopped; in children, puberty resumes once the medicine is stopped at an appropriate age.
Can it affect my bones?
Lowering sex hormones over a longer time can weaken bones, so your team may limit the course, add protective treatment, or check bone strength.
Authoritative sources
- BNF
- NICE CKS
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