Triptorelin

How does Triptorelin work?

Triptorelin binds GnRH receptors on the pituitary. The first exposure causes a big release of LH and FSH (the 'flare'), which pushes the testes to make more testosterone for a few days. With continuous exposure, as from a depot injection, the receptors desensitize and LH and FSH collapse, driving testosterone down to castrate levels within about 2 to 4 weeks. That is the whole point of the prostate cancer use. The single-dose restart idea tries to use only the flare: one short-acting dose stimulates the pituitary without enough ongoing exposure to shut it down. The catch is that the formulation matters enormously. A depot dose of triptorelin is designed to suppress testosterone for 1 to 6 months, which is the opposite of what someone trying to recover wants.

What does the research show?

For the approved uses, the evidence is solid. Trelstar labeling shows testosterone rising for the first few days, peaking on days 2 to 4, then falling to castrate levels (under 50 ng/dL) by weeks 3 to 4 in men with prostate cancer, with effects usually reversible after stopping. Triptodur is approved for central precocious puberty in children 2 and older. A 100 mcg triptorelin stimulation test is also an established diagnostic tool: a Chinese study of 229 males found LH peaked 45 to 60 minutes after the injection and that the peak level helped separate delayed puberty from hypogonadotropic hypogonadism. The HPTA restart use is much thinner. The best-known source is a 2010 Fertility and Sterility case report of one 34-year-old man with hypogonadism after internet-bought anabolic steroids: he got a single 100 mcg triptorelin test dose and his testosterone was back in the normal range within a month. That is one patient, no control group, and the dose was given as a diagnostic test, not as a treatment. A 2023 scoping review in Endocrine Connections found that gonadotropins usually recover on their own within 3 to 6 months after steroids stop, while testosterone recovery is often incomplete, and it did not identify triptorelin as a studied recovery treatment. Bottom line: plausible, cheap, and popular, but not proven to beat natural recovery or standard options.

What doses have been studied?

When and how is Triptorelin taken?

What are the side effects of Triptorelin?

Not everyone experiences these effects. Individual responses vary based on dosage, duration, and personal factors.

• ●Hot flushes (very common with depot use)
• ●Erectile dysfunction, low libido and testicular atrophy with ongoing suppression
• ●Temporary testosterone flare in the first days (can worsen prostate cancer symptoms)
• ●Prolonged testosterone suppression if a depot form is used by mistake
• ●Headache and skeletal pain
• ●Injection site pain
• ●Raised blood sugar, diabetes and lipid changes with long-term use
• ●Increased cardiovascular risk and QT prolongation with long-term androgen deprivation
• ●Hypersensitivity reactions, including anaphylaxis (rare)
• ●Convulsions (rare)
• ●Severe skin reactions such as Stevens-Johnson syndrome (rare, added to US label 2025)

References

• https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/020715s052lbl.pdf
• https://www.accessdata.fda.gov/drugsatfda_docs/label/2025/208956s014lbl.pdf
• https://pubmed.ncbi.nlm.nih.gov/20416868/
• https://pubmed.ncbi.nlm.nih.gov/21600174/
• https://pmc.ncbi.nlm.nih.gov/articles/PMC10620455/
• https://www.geneesmiddeleninformatiebank.nl/smpc/h33462_smpc.pdf

Frequently Asked Questions