Triptorelin dosage and evidence

What is Triptorelin?

How does Triptorelin work?

The body releases GnRH in pulses, and the receptor needs that rhythm to keep working. A slow-release shot keeps the receptor switched on all the time instead. At first that causes a surge of hormones, and testosterone or estrogen rises over the first days. Then the receptor wears out and pulls back. Hormone output falls, and testosterone or estrogen drops to castration levels within about two to four weeks. It wears off after stopping, though recovery can be slow after long use.

What have studies in people found about Triptorelin?

Big and steady on hormone suppression. Thin to missing on real health outcomes. Testosterone falls to castration levels in about nine of ten men and stays there. In children with early puberty, the key hormone is held down in over 93 percent. No study compares triptorelin with another drug of its kind on survival.

• Pooled look at 920 men: testosterone below 20 ng/dL in 92, 93, 90 and 91 percent at months 3, 6, 9 and 12.
• Early puberty, 44 children, no comparison group: the key puberty hormone was back to a child's level in 93.2 percent at month 6 and 97.7 percent at month 12.
• Big studies such as GETUG-AFU 17 and the chemotherapy add-on study give triptorelin to both groups as background. So they are not evidence about triptorelin.
• No modern study has put it head to head against leuprolide, goserelin or degarelix on any health outcome.

What this does not tell you: Everything above is a hormone test. Testosterone below 20 ng/dL is the approval standard and what doctors check. But it is a stand-in. It does not tell you about survival on its own. The differences in suppression between these drugs are small enough that nobody has shown they matter for health. The children's study had 44 patients and no comparison group. It measured a hormone, not the outcome parents care about, which is adult height.

What do people who took Triptorelin report?

This is what real people say happened to them, good and bad. Nobody measured it. A report cannot tell a real effect from the lift people get just from expecting it to work, from a diet or training change made at the same time, or from what was really in the vial. We still put it near the top. It is the next best thing to a study in people: what happens when real people use it, including what goes wrong.

• The described use is a single small injection, commonly 100 mcg, meant as a one off kick to restart the body's own testosterone after it was shut down. It is explicitly contrasted with the multi milligram monthly amounts used clinically to shut that same axis down, and the difference between a pulse and continuous exposure is the whole basis of the idea.
• The approach rests on a very small number of published cases and people in these threads say so directly. Scepticism is prominent, including moderators questioning how much weight a single reported recovery can carry and noting that a clinician who once used this approach stopped.
• The objection raised repeatedly is that it lasts so long in the body that one shot may not act as a brief pulse at all. The shut down is described as lasting for days, and full recovery as taking a couple of weeks.
• Practical accounts describe a shot into the muscle rather than under the skin, and warnings circulate against repeating it within months.
• Outright dismissal of it as forum folklore appears alongside the enthusiastic accounts, and there is essentially no long term follow up in anything posted. Discussion drifts quickly to alternatives, which is itself a measure of how little first hand experience is on offer.

Sources: Testosterone restart threads on ExcelMale and EliteFitness, found by site-restricted search and read directly, September 2026. Nothing above is attributed to any specific post and no post is reproduced.

The state of the research

The evidence, in charts

The studies we cite

• Study in people2017
  Efficacy of Testosterone Suppression with Sustained-Release Triptorelin in Advanced Prostate Cancer

  Triptorelin reliably shuts testosterone down in men with advanced prostate cancer. Researchers pooled 920 men from nine studies and tracked testosterone for a year. About eight in ten were fully suppressed after one month, and about nine in ten from three months onward. This adds up nine studies. It is not one study where people were split into groups by chance, whatever the PubMed listing implies. There was no untreated group to compare against.

  Pooled analysis of 920 men from nine prospective studies, with testosterone as the primary endpoint. The proportion reaching testosterone below 20 ng/dL was 79 percent at month 1, then 92, 93, 90 and 91 percent at months 3, 6, 9 and 12. This is a pooled analysis of prospective studies, not itself a randomised trial, despite how PubMed indexes it, and it should not be cited as one.

  PMID 28028737 Advances in Therapy
• Study in people2016
  Efficacy and safety of triptorelin 6-month formulation in patients with central precocious puberty

  The six month injection held back puberty in children who had started it far too early. 44 children who had never been treated, 39 girls and five boys, were given the long acting form across 18 centres. By six months, 41 of them had hormone levels back in the prepubertal range, and by a year almost all did. Everybody knew what they were getting and there was no comparison group. What was measured is a hormone level, not how tall these children ended up as adults.

  International phase 3 study at 18 centres in the United States, Chile and Mexico, in 44 treatment-naive children, 39 girls and five boys. 41 of 44 (93.2 percent) had prepubertal stimulated luteinising hormone at or below 5 IU/L at month 6, rising to 97.7 percent at month 12. Note the design: non-comparative and open-label, with no control group, and the endpoint is hormone suppression rather than adult height.

  PMID 26887034 Journal of Pediatric Endocrinology and Metabolism
• Study in people2020
  Adjuvant radiotherapy versus early salvage radiotherapy plus short-term androgen deprivation therapy in men with localised prostate cancer after radical prostatectomy (GETUG-AFU 17): a randomised, phase 3 trial

  This trial is about when to give radiotherapy, not about triptorelin, and it found no advantage in giving it early. Triptorelin was the hormone treatment handed to both groups, so it was never the thing being tested. 424 men who had had prostate surgery were assigned to immediate radiotherapy or to waiting until their cancer marker rose. Six years on, about the same share in each group were free of events. The men treated immediately had far more urinary problems and erectile trouble. Read the assignment before reading the result.

  424 men randomised after radical prostatectomy to adjuvant radiotherapy or to early salvage radiotherapy on biochemical relapse, with triptorelin given as background androgen deprivation to both arms. 5 year event free survival was 92 percent against 90 percent (HR 0.81, 95% CI 0.48 to 1.36, log-rank p=0.42), so no advantage to treating immediately, while late grade 2 or worse genitourinary toxicity ran 59 percent against 22 percent. Enrolment was stopped early for unexpectedly low event rates. Triptorelin was never the variable under test, which is why this trial is frequently and wrongly listed as triptorelin evidence: it reports on radiotherapy timing.

  PMID 33002438 The Lancet Oncology
• Study in people2019
  Effect of Adding Docetaxel to Androgen-Deprivation Therapy in Patients With High-Risk Prostate Cancer With Rising Prostate-Specific Antigen Levels After Primary Local Therapy: A Randomized Clinical Trial

  The same trap again, and the answer was no. Hormone treatment went to everybody, and the thing actually being tested was whether adding chemotherapy helped. 254 men with high risk prostate cancer and a rising marker took part. Adding docetaxel did not delay the marker rising, and years later it had not delayed the cancer spreading either. Nearly half the men on chemotherapy got dangerously low white cell counts. This tells you about chemotherapy, not about triptorelin.

  The same pattern again. Androgen deprivation is the constant in both arms and docetaxel is the variable under test. A reader searching for randomised triptorelin trials will land on studies of this shape and should read the randomisation before reading the result.

  PMID 30703190 JAMA Oncology