Quick facts
- Class
- GnRH receptor agonist
- Brand names
- Trelstar, Decapeptyl
- Approved for
- Prostate cancer; (abroad) precocious puberty, endometriosis
- Administration
- Intramuscular depot
- Status
- FDA-approved (Trelstar)
- Drug class
- GnRH (LHRH) agonist
- Brand names
- Trelstar, Decapeptyl
- Form
- Depot injection (IM or SC)
- Notable use
- Central precocious puberty
Key takeaways
- Triptorelin (Trelstar, Decapeptyl) is a long-acting GnRH agonist depot injection.
- It causes an initial flare followed by sustained, reversible hormone suppression.
- Used in advanced prostate cancer and, in many regions, central precocious puberty.
- Side effects reflect low sex hormones, including hot flashes and possible bone density loss.
- It is an FDA-approved prescription drug administered by professionals.
Overview
Triptorelin, sold under brand names including Trelstar and Decapeptyl, is a synthetic analogue of gonadotropin-releasing hormone (GnRH). Like other agonists in this class, it is delivered as a long-acting depot injection, allowing dosing at intervals of several weeks or months depending on the formulation.
Triptorelin is used primarily in the treatment of advanced hormone-sensitive prostate cancer. Depending on the country and formulation, it is also used for endometriosis, uterine fibroids, female infertility protocols, and central precocious puberty in children, where early sex hormone production is suppressed to allow more typical development.
As a GnRH agonist, triptorelin produces an initial stimulation of hormone release, the flare, followed by sustained suppression. This shared mechanism places it alongside goserelin and leuprolide as a standard androgen deprivation option.
How it works
Triptorelin binds to GnRH receptors on the pituitary gland. Under natural conditions, GnRH is released in pulses to stimulate luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion, which regulate testosterone and estrogen production.
Because the depot delivers triptorelin continuously rather than in pulses, it initially provokes a surge in LH and FSH, briefly raising sex hormone levels. With sustained exposure, the pituitary receptors become desensitized, and LH and FSH secretion declines markedly. This leads to a sustained fall in testosterone in men and estrogen in women.
In children with central precocious puberty, this suppression halts the premature activation of the reproductive axis. In hormone-dependent cancers, reducing the hormones that fuel growth can slow disease activity. The suppression is generally reversible once treatment is discontinued.
Clinical evidence
Triptorelin has an established record in prostate cancer as a form of androgen deprivation therapy, used alone or in combination with radiotherapy or other agents. Its hormone-suppressing efficacy is comparable to other GnRH agonists, and depot formulations have been developed to extend dosing intervals.
In pediatric endocrinology, triptorelin is used and studied for central precocious puberty, where the goal is to pause premature pubertal progression. It has also been evaluated in gynecological conditions such as endometriosis and in assisted reproduction protocols, where controlled suppression of the natural cycle is useful.
Across these uses, the consistent finding is reliable, reversible hormone suppression. The appropriate role of triptorelin depends on the diagnosis, age, and treatment goals, and is determined by specialists rather than applied uniformly.
Dosing & side effects
Triptorelin is given as an intramuscular or subcutaneous depot injection by a healthcare professional, with the formulation and interval chosen according to the condition treated. This page does not provide dosing instructions.
Common side effects stem from low sex hormone levels and may include hot flashes, sweating, reduced libido, sexual dysfunction, mood changes, headache, and fatigue. Reduced bone mineral density can occur with prolonged use, and metabolic or cardiovascular factors may be monitored during long-term therapy. Injection-site reactions are possible.
In advanced prostate cancer, the initial testosterone flare may transiently worsen symptoms, so an anti-androgen is often co-administered at the start. In children treated for precocious puberty, clinicians monitor growth and pubertal markers. Patients and caregivers should discuss expected effects and monitoring with the care team.
Legal status
Triptorelin is an FDA-approved prescription medication and is authorized by regulators in many other countries, sometimes under different brand names and for varying indications. It is administered under medical supervision.
It is not available over the counter and is not intended for self-administration or non-medical use. Approved indications, which can include advanced prostate cancer and central precocious puberty, are defined by regulatory authorities and product labeling and may differ by region.
Because triptorelin requires professional administration and careful patient selection, particularly in children, it should be obtained only through legitimate medical channels and used under specialist guidance.
Frequently asked questions
How is triptorelin different from goserelin?
Both are GnRH agonist depots that suppress sex hormones after an initial flare. They differ in formulation, dosing interval, and approved indications by region, but share the same basic mechanism.
Why is triptorelin used in children?
In central precocious puberty, it suppresses the prematurely activated reproductive axis to pause early pubertal changes. This use requires close specialist monitoring of growth and development.
Does triptorelin cause an initial hormone surge?
Yes. Like other GnRH agonists, it briefly raises hormone levels (the flare) before producing suppression, which is why an anti-androgen may be used early in prostate cancer treatment.
Is the hormone suppression reversible?
Generally yes. Hormone levels usually recover after treatment stops, though the timing varies with the individual and the duration of therapy.
Is triptorelin chemotherapy?
No. It is a hormonal therapy that lowers sex hormone levels rather than a cytotoxic chemotherapy drug, though it may be combined with other treatments.
References
Each source links to its original record — peer-reviewed studies, regulator pages, or reference texts, labelled by type. We summarize findings neutrally; a citation is a reference, not an endorsement, and not a claim that its authors reviewed this page.
- Leone Roberti Maggiore U, Scala C, Remorgida V, et al. Triptorelin for the treatment of endometriosis. Expert Opin Pharmacother. 2014. Peer-reviewed study
- Keating GM. Triptorelin embonate (6-month formulation). Drugs. 2010. Peer-reviewed study
- Bertelloni S, Mucaria C, Baroncelli GI, et al. Triptorelin depot for the treatment of children 2 years and older with central precocious puberty. Expert Rev Clin Pharmacol. 2018. Peer-reviewed study
- Frampton JE. Triptorelin: A Review of its Use as an Adjuvant Anticancer Therapy in Early Breast Cancer. Drugs. 2017. Peer-reviewed study
- Ploussard G, Mongiat-Artus P. Triptorelin in the management of prostate cancer. Future Oncol. 2013. Peer-reviewed study
- Lu X, Sun Y, Han M, et al. Triptorelin nanoparticle-loaded microneedles for use in assisted reproductive technology. Drug Deliv. 2023. Peer-reviewed study