Recovery & HealingAlso known as: Trelstar, Decapeptyl, GnRH Agonist

Triptorelin

Synthetic GnRH agonist used in post-cycle therapy (PCT) to restore endogenous testosterone production.

Half-Life

~3-5 hours

Dose Range

100 mcg (single dose PCT)

Frequency

Single dose (PCT)

Vial Sizes

0.1 mg

🔬 Mechanism of Action

Triptorelin is a synthetic GnRH agonist decapeptide used in post-cycle therapy (PCT) to restart the hypothalamic-pituitary-testicular axis (HPTA) after anabolic steroid or SARM suppression.

A single low-dose (100 mcg) subcutaneous injection causes a powerful LH/FSH surge by overstimulating GnRH receptors. This "pituitary restart" can restore natural testosterone production in as little as 72 hours. At higher or continuous doses, triptorelin paradoxically suppresses the HPTA — this is exploited clinically (Trelstar) for prostate cancer treatment.

Source: PMID: 15483224

📜Background & History

Triptorelin is a synthetic GnRH decapeptide analog (D-Trp6 substitution) used medically as a depot injection for prostate cancer (via GnRH receptor desensitization causing chemical castration), endometriosis, uterine fibroids, and precocious puberty. In performance medicine, it is used off-label in single low-dose administration (100 mcg) to trigger a massive LH surge for HPG axis restart ("triptorelin PCT") after suppression from androgens or other hormones.

🎯 Research Use Cases

✓Post-cycle therapy: single low-dose HPG axis restart after prolonged androgen suppression
✓Prostate cancer treatment (depot formulation)
✓Endometriosis and uterine fibroid management (depot)

💉 Dosing Protocol

Typical Dose	100 mcg (single dose PCT)
Frequency	Single dose (PCT)
Half-Life	~3-5 hours
Common Vial Sizes	0.1 mg

🧪 Reconstitution Example

Vial

0.1 mg

Water

1 mL

Concentration

0.1 mg/mL

Per Unit (100u syringe)

1 mcg

Dose of 100 mcg = 100 units on a 100-unit insulin syringe

🧮 Calculate Your Exact Triptorelin Dose →

⚠️Safety & Considerations

FDA-approved (Trelstar) at high doses for prostate cancer. For PCT: use ONLY a single 100 mcg dose. Repeated or higher doses will cause chemical castration (HPTA suppression). This is NOT a peptide for ongoing use.

⚡Interactions & Contraindications

Single low-dose PCT use and depot therapeutic use have opposite mechanisms (pulsatile vs continuous GnRH → stimulation vs suppression). Antiandrogens interact with the testosterone response post-triptorelin. Do not combine with other GnRH analogs.

🔗Synergies & Common Stacks

+ Gonadorelin

Triptorelin provides the initial LH surge for HPG restart; Gonadorelin pulsatile dosing then maintains axis activity through recovery phase.

Triptorelin dosing guide infographic showing dose range 100 mcg (single dose PCT), half-life ~3-5 hours, and reconstitution example — Triptorelin dosing quick reference — 100 mcg (single dose PCT), Single dose (PCT)

❓ Frequently Asked Questions

Why is a single dose of triptorelin used for PCT?▼

A single 100 mcg dose creates a massive LH/FSH surge that "restarts" the suppressed HPTA. Repeated or higher doses will paradoxically shut down the axis — so it is CRITICAL to use only one dose. This is a powerful tool that requires precision.

Is triptorelin safer than Clomid/Nolvadex for PCT?▼

Different mechanism — triptorelin provides a single sharp restart vs SERMs that require weeks of daily dosing. Some users prefer triptorelin for its speed and simplicity. However, the margin for error is razor-thin. Consult with an endocrinologist.

📖 References

Carel JC, et al. “Triptorelin for treatment of central precocious puberty.” Pediatrics (2009). PMID: 19948620

← Back to Peptide Library