Quick summary
Alarelin is a synthetic GnRH agonist several times more potent than native GnRH, developed and approved in China for triggering ovulation in assisted reproductive technology. It is not approved in the US or EU but is widely used in Chinese IVF and ART protocols.
Overview
Alarelin is a synthetic nine-amino-acid GnRH (gonadotropin-releasing hormone) agonist developed and approved in China for controlled ovarian hyperstimulation in assisted reproductive technology (ART). It is several times more potent than native GnRH and is used to trigger ovulation in IVF and other ART protocols. It is not approved in the US or EU but is widely used in Chinese reproductive medicine.
Mechanism of action
Alarelin binds with high affinity to GnRH receptors (GnRHR) in pituitary gonadotroph cells, initially stimulating a surge release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). In acute use, this LH surge triggers final oocyte maturation and ovulation, making it useful as a trigger shot in antagonist IVF cycles. Chronic administration, like other GnRH agonists, leads to GnRHR downregulation and pituitary desensitization, resulting in hypogonadal suppression. Alarelin's biological activity in gonadotropin secretion stimulation is described as many times greater than native GnRH in both in vivo and in vitro rat pituitary models. The D-amino acid substitution in its structure (similar to other GnRH agonists) confers resistance to enzymatic degradation and prolonged receptor binding.
Dosing protocols
| Purpose | Route | Dosage | Frequency | Notes |
|---|---|---|---|---|
| ovulation triggering in ART (China-approved protocol) | subcutaneous | 200–400 mcg | single dose for ovulation trigger | Used as trigger in GnRH antagonist IVF cycles. Timing is critical: 36–38 hours before oocyte retrieval. |
| controlled ovarian stimulation research | nasal | 300–600 mcg | twice daily for down-regulation | Intranasal route is used in some Chinese protocols for pituitary down-regulation prior to ART stimulation. |
Dosing information is for educational purposes only. Consult a qualified healthcare professional before using any peptide.
Research summary
Alarelin has been studied extensively in Chinese clinical trials for ART applications including IVF, controlled ovarian hyperstimulation (COH), and intrauterine insemination (IUI). Chinese studies demonstrate equivalent or superior oocyte retrieval rates versus hCG triggers, with potentially lower risk of ovarian hyperstimulation syndrome (OHSS) in certain protocols. Animal studies in sheep demonstrate enhanced follicular development and modulation of gonadotropin receptor expression. The research base is primarily Chinese-language publications; limited English peer-reviewed data is available. Active immunization studies with alarelin in sheep show durable suppression of reproductive function.[1][2][3]
Evidence grading
Each claimed benefit is graded by the strength of available evidence. Grades reflect study quality, not effect size.
Strong = multiple RCTs · Moderate = limited trials or observational · Preliminary = animal or in vitro only · Insufficient = anecdotal or no published data
Side effects
Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.
Common stacks
Peptides commonly paired with Alarelin for synergistic effects.
Legal status
Approved in China for use in assisted reproductive technology. Not approved by FDA or EMA. Available in Western markets as a research chemical. Any use outside approved Chinese clinical contexts is for research purposes only.
Sourcing & access
Research compound
Alarelin is classified as a research compound. Regulatory status varies by jurisdiction. Always verify current legal status and source from vendors providing third-party certificates of analysis (COA).
Frequently asked questions
Alarelin is a synthetic nine-amino-acid GnRH agonist used in China for controlled ovarian hyperstimulation in IVF and other assisted reproductive technology protocols. It is several times more potent than native GnRH due to a D-amino acid substitution that confers enzymatic resistance.
Alarelin binds GnRH receptors in the pituitary, initially triggering an LH and FSH surge that can be used to trigger ovulation. Chronic administration leads to receptor downregulation and pituitary desensitization, resulting in hypogonadal suppression.
No, Alarelin is not approved by the FDA or EMA. It is approved in China for assisted reproductive technology and is available in Western markets only as a research chemical.
Reported side effects include hot flashes, headache, nausea, injection site redness, mood changes, and temporary pituitary suppression. Like other GnRH agonists used in assisted reproduction, Alarelin carries a risk of ovarian hyperstimulation syndrome when used in controlled ovarian stimulation protocols, and Chinese clinical trials suggest this risk may be lower than with hCG triggers in specific antagonist cycles.