Gonadorelin Dosing: 100mcg SubQ vs 10mcg/90min

Gonadorelin is the rare compound where the delivery pattern, not the dose, decides whether it stimulates or suppresses. Delivered in physiologic pulses — the published clinical protocols start at 10 mcg every 90 minutes through a portable subcutaneous pump — it drives luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release. Delivered continuously, the identical molecule downregulates pituitary GnRH receptors and shuts gonadotropin output down. That is not a side effect or an edge case; it is the mechanism long-acting GnRH agonists use to produce medical castration.

The figure circulating in community and telehealth-clinic use is different: roughly 50-200 mcg injected subcutaneously two to three times per week. This guide reports both, keeps them separate, and is explicit that the published efficacy evidence sits behind the pump protocol — not the twice-weekly injection.

Research-context information only. Gonadorelin is the active ingredient in FDA-approved products for evaluating hypothalamic-pituitary-gonadal function and for inducing ovulation in hypothalamic amenorrhea; research-peptide and compounded forms are not FDA-approved and are sold for research purposes only. Protocols, doses, and reactions reported below come from clinical trials and community sources. This article reports what has been documented, not what should be done. Consult a licensed physician for personal medical decisions.

Gonadorelin is a synthetic decapeptide identical in sequence to endogenous gonadotropin-releasing hormone (pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2). What follows covers the documented pulsatile protocols, the community subcutaneous figures, reconstitution and syringe-unit math, and where the two diverge.

Pattern Beats Dose: Pulsatile Stimulates, Continuous Suppresses

This is the single most important fact about dosing gonadorelin, and it is not optional context.

In 1978, Belchetz and colleagues gave GnRH to rhesus monkeys with hypothalamic lesions. Intermittent delivery — one pulse per hour — reestablished pituitary gonadotropin secretion. Constant infusion of the same hormone, at comparable total exposure, failed to sustain it. Their conclusion was that the effect was attributable to the pattern of delivery rather than the amount of hormone the pituitary saw (PMID 100883).

The receptor biology behind this is well characterized. Gonadorelin binds the type-I GnRH receptor on anterior pituitary gonadotrophs, a Gq/11-coupled G-protein-coupled receptor; the coupling activates phospholipase C, which drives the inositol-phosphate and calcium signaling that releases LH and FSH (Hsieh & Martin, 1992, PMID 1333052). Under intermittent stimulation, the receptor population resets between pulses. Under continuous, non-physiologic stimulation, GnRH receptors downregulate and desensitize, gonadotropin secretion falls sharply, and testosterone drops toward castrate levels — the documented mechanism of depot GnRH-agonist therapy in prostate cancer (Eckstein & Haas, 2014, PMID 24756149).

Two practical consequences follow. First, "more gonadorelin" is not directionally the same as "more LH" — beyond a point, sustained exposure reverses the effect. Second, any protocol that changes the delivery interval is changing the pharmacology, not just the intensity.

Quick Reference: Documented Protocols

The figures below come from two different source classes and are kept apart deliberately. Only the first has published efficacy evidence attached to it.

Clinical protocol (pump-delivered pulsatile GnRH, congenital hypogonadotropic hypogonadism):

Community protocol (self-administered subcutaneous injection, adjunct use alongside testosterone therapy):

The arithmetic gap between the two is the part worth sitting with. The trial pump delivers roughly 112 discrete pulses per week; the community protocol delivers 2 or 3. The clinical protocol is not a larger version of the community one, and the community one is not a scaled-down version of the clinical one — they are different pharmacology.

Cycling and Frequency

There is no established on/off cycle for gonadorelin in the clinical literature. The pump protocols in congenital hypogonadotropic hypogonadism run continuously for months, with the pulse interval — not a weekly on/off pattern — doing the work of preserving receptor sensitivity. Hao et al. titrated from a 10 mcg / 90 minute starting point based on LH, FSH, and testosterone response (PMID 34277762); testosterone in that cohort did not rise until roughly one month into therapy, which is a useful marker of how slowly the axis responds.

Community sources describe indefinite adjunct use rather than defined cycles, generally continuing for as long as testosterone therapy continues. Some community and clinic sources raise receptor downregulation as a reason for spacing doses at least two days apart; that reasoning is mechanistically consistent with the Belchetz findings, but no trial has tested whether a 2-3x weekly interval preserves or erodes gonadotroph responsiveness over time.

Routes of Administration

Subcutaneous infusion (the trial route). Every published efficacy protocol cited here used a portable pump delivering subcutaneous micro-pulses. This is the only route with spermatogenesis and gonadotropin outcome data behind it.

Subcutaneous bolus injection (the community route). Self-administered abdominal or thigh injections with a 29-31 gauge insulin syringe, at volumes of roughly 0.05-0.2 mL depending on dilution. Community and telehealth-clinic sources describe this as how research-market gonadorelin is used outside a clinical, FDA-approved protocol.

Intravenous bolus (the diagnostic route). The GnRH stimulation test, used to assess hypothalamic-pituitary-gonadal axis function, is performed as a single 100 mcg intravenous bolus with LH and FSH sampled at fixed intervals afterward. It is a one-time diagnostic provocation, not a therapeutic protocol, and it is worth distinguishing from either pattern above. The historical US-approved diagnostic and pulsatile-fertility products have both been discontinued; current domestic supply is compounded or research-market material rather than an FDA-approved finished product.

Not oral. As a decapeptide, gonadorelin is degraded in the gastrointestinal tract; no oral route appears in the clinical record.

Reconstitution Quick Reference

Math: 2,000 mcg / 2 mL = 1,000 mcg/mL. 100 mcg / 1,000 mcg per mL = 0.1 mL = 10 units on a 100-unit insulin syringe.

Community reconstitution references describe directing the water down the vial wall, swirling gently rather than shaking, refrigerating at 2-8°C, and using within 28 days. Gonadorelin's instability in solution is one reason the clinical pump protocols reload the reservoir on a short schedule.

These figures describe community-documented practice, not a recommended procedure — see the research-context note above.

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Where These Numbers Come From

The 10 mcg / 90 minute figure is not a community convention — it is the starting dose in the published pump studies. Hao et al. (2021) ran a prospective multicentre study across three Chinese hospitals in 28 male patients with congenital hypogonadotropic hypogonadism, initiating subcutaneous pulsatile GnRH at 10 mcg per 90 minutes and reporting LH rising to 1.71 ± 0.96 IU/L by day 4 and 2.66 ± 1.74 IU/L by day 7, with FSH rising to 3.19 ± 1.84 and 5.05 ± 3.03 IU/L over the same window (PMID 34277762). Notably, testosterone in that cohort did not move until about a month in — the gonadotropin response comes first, the gonadal response lags.

Zhang et al. (2019) compared a pulsatile gonadorelin pump against cyclical gonadotropin therapy in 28 azoospermic men with congenital hypogonadotropic hypogonadism (10 pump, 18 gonadotropin) and reported spermatogenesis at a median of 6 months on the pump versus 14 months on gonadotropin therapy, with sperm appearing in 90% and 83.3% of the two groups respectively (PMID 30569789). Huang et al. (2024) took the harder population — 28 patients who had responded poorly to roughly 12.5 months of combined gonadotropin therapy — switched them to pulsatile GnRH at 10 mcg per 90 minutes, and detected sperm in 17 of 28 (60.7%), with mean testicular volume rising from 3.93 mL to 8.45 mL (PMID 38739523).

Pooling this literature, Wei et al. (2021) analysed 8 articles from 7 studies covering 420 patients and concluded that pulsatile GnRH was associated with earlier spermatogenesis and larger testicular volume than gonadotropin therapy, but with no significant difference in final sperm detection rate, sperm concentration, or pregnancy rate (PMID 32777865).

Two boundaries on all of this. Every one of these studies is in diagnosed congenital hypogonadotropic hypogonadism — a population with an intact pituitary and an absent hypothalamic signal, which is the exact deficit pulsatile GnRH is designed to replace. And every one of them delivered the peptide by pump.

Why the Community Protocol Is Not the Trial Protocol

The honest version of this section is short: a 100 mcg subcutaneous injection twice a week does not reproduce what the trials did, and reporting the trial outcomes next to the community figure without saying so would be misleading.

Three specific gaps. Pulse count: the trial pumps deliver roughly 16 pulses per day; twice-weekly dosing delivers 2 pulses per week. Persistence: published pharmacokinetic reviews of GnRH and its analogues describe a plasma half-life measured in minutes rather than hours (Handelsman & Swerdloff, 1986, PMID 3007081), with product pharmacokinetic data giving a distribution half-life of roughly 2-10 minutes and a terminal half-life of roughly 10-40 minutes. A single subcutaneous dose therefore produces one gonadotropin pulse lasting a few hours, followed by three or four days of no exposure at all. Population: the outcome data come from men with a diagnosed hypothalamic defect, not from men with a suppressed axis secondary to exogenous testosterone.

That does not make the community pattern pharmacologically inert — a bolus of GnRH does provoke an LH and FSH pulse, which is the basis of the diagnostic stimulation test. It means the effect size, durability, and downstream outcomes of that pattern are undocumented. Community sources report using it to maintain testicular function during testosterone therapy; that use has no controlled trial behind it, and clinic-side sources themselves describe response as inconsistent between individuals.

Stacking and Combination Use

Note the direction of the mechanism when comparing options: gonadorelin acts at the pituitary and requires an intact gonadotroph response, while hCG bypasses the pituitary entirely. Documented protocols treat them as different points of intervention on the same axis, not as a stack.

Side Effects and Safety

• Injection-site and infusion-site reactions — the most commonly documented local effect, and the practical limiter on continuous pump wear.
• Allergic reactions — reported in the GnRH arms and not the gonadotropin arms in the Wei et al. meta-analysis of 420 patients (PMID 32777865).
• Receptor downregulation with non-physiologic delivery — the documented consequence of continuous rather than pulsed exposure, and the mechanism behind GnRH-agonist medical castration (PMID 24756149).
• Gonadotropin surge effects — depot GnRH-agonist literature describes an initial testosterone flare before suppression sets in; the same directional biology is why delivery pattern is monitored closely in clinical use (PMID 24756149).
• Slow gonadal response — testosterone did not rise until roughly one month into pump therapy in the Hao cohort (PMID 34277762), so early bloodwork can read as non-response.
• Sourcing and sterility — research-market material is not pharmaceutical-grade; purity, fill accuracy, and sterility are unverified without a batch-matched certificate of analysis.

mg to Units Conversion

Conversion reference (community-documented dilutions): these reflect dilutions described in community reconstitution references — not a prescribed dosing schedule.

On a standard 100-unit insulin syringe, each unit equals 0.01 mL, so 100 units equals 1 mL. Once gonadorelin is reconstituted, the conversion from a target dose to syringe units depends entirely on the chosen dilution.

Reconstitution A: 2 mg vial + 2 mL BAC water (1,000 mcg/mL) — the standard dilution from the Quick Reference above.

Reconstitution B: 2 mg vial + 3 mL BAC water (~667 mcg/mL) — more water for larger, easier-to-measure draws.

These conversions reflect the dilutions documented in community reconstitution protocols. They report how the math is described, not a recommended dosing schedule.