Last Updated January 22, 2024

 January 22, 2024

Gonadorelin is a gonadotropin-releasing hormone (GnRH) agonist that may be used to prevent testicular shrinkage and infertility in men undergoing testosterone replacement therapy.

It has long standing clinical use in general fertility medicine, and is one of the better-studied synthetic GnRH analogs. The peptide is most commonly administered via subcutaneous injection, in some cases with a portable infusion pump.

Yet research indicates that gonadorelin in the form of nasal spray provides adequate bioavailability and represents a noninvasive alternative to injections.

Given the unique advantages of intranasal peptide delivery, our research team has published this comprehensive review on gonadorelin nasal spray.

Read on as we discuss the potential benefits and side effects of gonadorelin and reveal our pick of the best gonadorelin nasal spray online.

Buy Gonadorelin Nasal Spray from our top-rated vendor...

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What is Gonadorelin?

Gonadorelin is a synthetic version of gonadotropin-releasing hormone (GnRH), which is naturally synthesized and released within the hypothalamus, and regulates the release of the reproductive hormones follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

Gonadorelin is clinically used to treat hypogonadism, testicular atrophy, male infertility, low libido, and hormonal irregularities, among a range of conditions [1].

Gonadotropins like FSH and LH are glycoprotein hormones that are central to the endocrine system and its ability to regulate growth, reproduction, and sexual development. Present in both men and women, gonadotropins act directly on the gonads, controlling sex hormone production.

Gonadotropins are not generated in the gonads themselves, but in the pituitary gland in response to GnRH, while GnRH is produced in the hypothalamus. The “axis” of hormone regulation is referred to as the hypothalamus-pituitary-gonad-axis [2].

Gonadorelin sold as a research chemical is intended for use only by qualified researchers for in vitro testing and laboratory experimentation only.


Gonadorelin Nasal Spray


Gonadorelin Benefits

GnRH controls a very complex process of spermatogenesis in males and ovulation in females. It has an exceptionally short terminal half-life of 10-40 minutes, which traditionally requires infusion pumps for clinical use.

In men, LH and FSH are essential to normal endogenous testosterone production and help protect fertility, maintaining spermatogenesis. GnRH causes the release of both hormones.

Conversely, in women LH and FSH contribute to estrogen production. In women undergoing chemotherapy, GnRH appears to protect the function of the ovaries [3].

As a GnRH agonist, gonadorelin is thus commonly viewed as a fertility treatment in both men and women. Research has established the therapeutic potential of gonadorelin across other contexts, as we discuss below.

Male Infertility and Sex Hormone Levels

Men on testosterone replacement therapy (TRT) often resign themselves to testicular shrinkage and loss of fertility as a “trade-off” for the benefits associated with testosterone optimization.

Both LH and FSH contribute to the release of testosterone in men, or estrogen and progesterone in women. We can clearly see from studies that exogenous testosterone enhances gonadotropin suppression in male patients on TRT and leads to testicular shrinkage. In this context, the administration of gonadorelin enables the controlled release of LH and FSH to help maintain spermatogenesis and fertility. [4, 5].

Modulation of the hypothalamic-pituitary-gonadal axis (HPG) is critical to the treatment of male infertility. Without GnRH, the pituitary stops making LH while on TRT. This leads to suppressed endogenous testosterone production, and testicular atrophy. Research indicates that GnRH treatment can restore testicular function in cases of suppression while protecting against testicular atrophy [6].

Gonadorelin has similarly been studied as a tool for increasing sperm production and motility, optimizing spermatogenesis from stimulation of Sertoli cells, and normalizing the testosterone-to-estrogen ratio in men [7, 8, 9].

Breast Cancer and Fertility in Women

Gonadorelin is currently being studied as a treatment option for estrogen-receptor positive breast cancer, and for its ability to preserve fertility in women undergoing chemotherapy.

A review of patient data across 224 women documented that GnRH and GnRH analogs improved the complete tumor remission rate of breast cancer. The gonadotropin-releasing hormone receptor (GnRHR) is expressed in various types of malignant tumors and inhibits the proliferation of cancer cells [10].

GnRH and analogs are increasingly being used as a treatment option for advanced breast cancer patients with functioning ovaries that are pre- and perimenopausal. A review published in Frontiers in Oncology demonstrates a higher recurrence-free survival rate, overall survival rate, and protection of fertility while undergoing chemotherapy when GnRH is given in tandem with traditional treatment methods [11].


Gonadorelin Side Effects

Since gonadorelin has not undergone any large-scale safety studies, it is not possible to determine all potential side effects of gonadorelin at this time.

However, gonadorelin and GnRH analogs have been administered to human and animal populations in both randomized and controlled studies, with no deleterious effects reported.

The peptide appears to be safe and well-tolerated when professionally administered using injectable or intranasal routes of delivery [12, 13, 14].

Minor side effects have been noted in the research, including:

  • Headaches
  • Skin flushing
  • Nausea and abdominal discomfort
  • Pain, swelling, or tenderness at the injection site
  • Dizziness

Similarly, human chorionic gonadotropin (hCG), another gonadotropin-releasing hormone agonist, was found to have a high safety profile.

In one patient report involving a 44-year-old hypogonadal male, hCG administered at 1,500 IU twice weekly for 24 weeks, together with recombinant FSH (150 IU 3 times a week), resulted in improved hormone levels and normal sperm concentration. No deleterious side effects were reported [15].

As gonadorelin stimulates sex hormone production, administration could exacerbate any condition made worse by increased androgen production.

A rare condition called gonadotropin-releasing hormone adenoma may also worsen from use of gonadorelin. In such cases, gonadorelin may cause problems in the pituitary gland, resulting in sudden blindness. Most gonadotropin-secreting adenomas do not cause any symptoms and are benign [16]. This condition should be ruled out in potential subjects prior to conducting gonadorelin research.


Gonadorelin Dosage Guide | Nasal Spray

As gonadorelin is not currently approved for human use, there are no official dosing guidelines in place for this compound.

Dosing will vary based on the purpose of the research study. Based on current studies, researchers are encouraged to consider the following points when administering gonadorelin:

  • Generally, daily subcutaneous gonadorelin doses range from 5mcg to 20mcg. Doses may be titrated upward to up to 25mcg as needed.
  • Intranasal doses of 90mcg per day (15mcg in each nostril, 3 times per day) of Buserelin, a related GnRH analog, appeared effective at restoring testicular function and spermatogenesis in an infertile man after one year of treatment [17].
  • Long-term administration may be required in cases of hypogonadotropic hypogonadism or fertility preservation for men on TRT.
  • Gonadorelin and GnRH analogs have a favorable safety profile, even when used long-term (12-24 months) [18]. The optimal dosing schedule will depend upon the desired clinical outcome and body mass of the subject(s).

Sample Gonadorelin Nasal Spray Dosing Protocol

For reference, we are including a sample dosing protocol for researchers studying gonadorelin and using a nasal spray that contains 100mcg of gonadorelin per dose (spray). This is comparable to the gonadorelin nasal spray offered by our preferred vendor.

Assuming the above, the researcher may administer as follows:

  • Gonadorelin Dosage: 400mcg total per day (1 spray into each nostril qAM, and 1 spray into each nostril qPM).
    Course Duration: Administer as needed.
  • Notes: One 10mg spray bottle represents a 25-day supply following this dosing protocol. Researchers can adjust dosing or duration depending on the severity of condition, clinical outcome, or research methodology.

As research on this peptide is continually expanding, researchers are advised to stay informed on the latest developments and recommendations regarding gonadorelin and intranasal delivery.


Gonadorelin Nasal Spray | A Comprehensive Review

Gonadorelin is typically administered via subcutaneous injection for maximum bioavailability, yet in some cases researchers may opt for a nasal spray depending on the study design.

Intranasal Gonadorelin Delivery

Clinical researchers have demonstrated that intranasal administration may help peptides more easily enter the brain. Researchers have long established that nasal formulations may be a suitable alternative for delivering medication [19].

In a study involving Fowler’s toads, intranasal administration of a gonadotropin releasing hormone analog (GnRHa) successfully raised sperm production in the test subjects, leading the researchers to conclude on the viability of GnRHa nasal administration [20].

A fertility study across 82 women found that a single dose nasal spray of GnRH was just as effective as an intramuscular hCG injection to mature oocytes as part of a controlled ovarian stimulation protocol [21].

Further research involving the GnRH analog Buserelin demonstrated that intranasal administration (400 mcg 3x daily) resulted in higher testosterone levels compared to subcutaneous injection as part of a year-long study in men with prostate cancer [22].

We can extrapolate these findings to the potential of intranasally administered gonadorelin in contexts of fertility preservation and sex hormone regulation in both men and women.

Benefits of Intranasally Administered Gonadorelin

There are a number of potential benefits of gonadorelin intranasal delivery:

  • Intranasally administered gonadorelin can be delivered directly to the brain, bypassing the BBB. This could allow for targeted treatment, depending on the research methodology.
  • Gonadorelin is poorly absorbed orally and intranasal administration allows for a much higher degree of absorption.
  • Potentially unwanted side effects associated with intramuscular or subcutaneous injections can be avoided, such as injection site pain and irritation.
  • Intranasal delivery of gonadorelin is simple. If ultimately approved for clinical use, it can be administered by patients themselves. This would potentially minimize the amount of daily injections required, or the fitting of an infusion pump. It also would reduce barriers to treatment.

Precautions with Gonadorelin Nasal Spray

Researchers who wish to administer gonadorelin as a nasal spray should take note of certain precautionary measures to ensure optimal bioavailability.

  • Ensure the subject’s head is tilted upward for proper administration.
  • Wait 1-2 minutes between repeating sprays in the same nostril to mitigate the risk of oversaturation.
  • The nozzle of the spray bottle needs to be kept sterilized and clean at all times to prevent degradation or contamination of the product.
  • Gonadorelin is stable for several months at room temperature and this peptide can be stored in the refrigerator, but should not be frozen.

Aside from the aforementioned guidelines, researchers should ensure that they purchase gonadorelin from a reputable supplier.

Important factors to consider when purchasing gonadorelin nasal spray include evaluating any third-party laboratory tests done on the purity of the product and assessing customer feedback on the vendor.


Gonadorelin Nasal Spray


Where to Buy Gonadorelin Nasal Spray Online?

Researchers looking to source high-quality gonadorelin nasal spray online have a number of potential options.
To ensure safety in experimentation, it is crucial to carefully vet vendors based on their certifications, reputation, and production standards.

In our professional experience, PureRawz stands out for their peptide-based nasal sprays, including their gonadorelin nasal spray.

Here are some of the reasons as to why we endorse PureRawz:

  • Lab-Tested Peptides: PureRawz has an established track record of using strict in-house testing in addition to third-party lab testing to ensure that their products are pure and contaminant-free.
  • Fast Shipping: PureRawz is based out of the U.S. and delivers orders within 2-3 business days to domestic customers. Researchers ordering from the UK or Australia have options for expedited shipping.
  • Affordable Pricing: PureRawz products are well-priced and their 10mg gonadorelin nasal spray currently retails for just under $131. The vendor regularly offers promo and discount codes through their social media platforms.
  • Reliable Customer Service: PureRawz offers 24/7 customer support through both online live chat or email. They are also easily accessible via major social media platforms.

Buy Gonadorelin Nasal Spray from our top-rated vendor...


Gonadorelin Nasal Spray vs. Injectable Gonadorelin

It is well-established that peptides generally have poor oral bioavailability (as low as <2%), due to the physiological environment of the digestive system. This holds true for synthetic GnRH and its derivatives, like gonadorelin [23, 24].

Thus, researchers interested in testing gonadorelin may wonder whether they should opt for an injectable version or gonadorelin nasal spray.

Injectable Gonadorelin | Bioavailability

The primary reason for opting for injectable gonadorelin rather than gonadorelin nasal spray is bioavailability.

In a study published in The Journal of Clinical Endocrinology & Metabolism, hypogonadal men were given varying doses of exogenous GnRH over a 12-24 month period, administered subcutaneously using a portable infusion pump. The injections were successful in normalizing luteinizing hormone levels in 97% of the volunteers and testosterone levels in 93% of the group, demonstrating the efficacy of long-term gonadorelin injection treatment [25].

We must make note of the exceptionally short half-life of gonadorelin, which is between 2-10 minutes depending on how quickly it is metabolized. For this reason, gonadorelin has traditionally been administered using a portable infusion pump or intravenously [7, 8, 9].

Gonadorelin Nasal Spray | Accessibility

In certain research settings, a nasal spray represents an alternative route of delivery that does not require peptide reconstitution or usage of a portable infusion pump [19, 26]. Some of the benefits of this route of delivery include:

  • Easier, more convenient, and less invasive form of administration
  • More suitable for regular use
  • Sprays are delivered in predetermined doses

Regardless of these unique benefits of gonadorelin nasal spray, researchers seeking maximum bioavailability are advised to consider gonadorelin injections.

In our experience, this is a trustworthy vendor is a trustworthy provider of injectable gonadorelin and other research peptides.


Gonadorelin Nasal Spray | Verdict

Gonadorelin is an analog of gonadotropin-releasing hormone that is clinically used in fertility medicine and to treat hypogonadism. It is also used to delay or prevent testicular atrophy associated with testosterone replacement therapy in men.

While gonadorelin is most commonly administered via injection, intranasal delivery of the GnRH analog is an alternative route that may be suitable in certain settings. Gonadorelin nasal spray is less invasive than traditional subcutaneous administration and may be delivered in a convenient, metered spray bottle.

Based upon our testing criteria and experience, our team recommends PureRawz as the best vendor of gonadorelin nasal spray online.


References

  1. Studying the effects of 7 days of gonadotropin releasing hormone (GnRH) treatment in men with hypogonadism – full text view (no date) Full Text View – ClinicalTrials.gov. Available at: https://clinicaltrials.gov/ct2/show/NCT00493961 (Accessed: March 27, 2023).
  2. Klein CE. The Hypothalamic-Pituitary-Gonadal Axis. In: Kufe DW, Pollock RE, Weichselbaum RR, et al., editors. Holland-Frei Cancer Medicine. 6th edition. Hamilton (ON): BC Decker; 2003. Available from: https://www.ncbi.nlm.nih.gov/books/NBK13386/.
  3. Hickman LC, Valentine LN, Falcone T. Preservation of gonadal function in women undergoing chemotherapy: a review of the potential role for gonadotropin-releasing hormone agonists. Am J Obstet Gynecol. 2016 Oct;215(4):415-22. doi: 10.1016/j.ajog.2016.06.053. Epub 2016 Jul 13. PMID: 27422055.
  4. Flanagan, C. A., & Manilall, A. (2017). Gonadotropin-Releasing Hormone (GnRH) Receptor Structure and GnRH Binding. Frontiers in endocrinology, 8, 274. https://doi.org/10.3389/fendo.2017.00274.
  5. Bhasin S, Heber D, Steiner B, et al. Hormonal effects of GnRH agonist in the human male: II. Testosterone enhances gonadotropin suppression induced by GnRH agonist. Clin Endocrinol (Oxf). 1984;20(2):119-128. doi:10.1111/j.1365-2265.1984.tb00066.x.
  6. Gautier, C. et al. (2022) “Re-stimulation of testicular function in gnrh-vaccinated stallions by daily GnRH agonist treatment,” Theriogenology, 194, pp. 27–34. Available at: https://doi.org/10.1016/j.theriogenology.2022.09.011.
  7. Conn, P. M., & Crowley, W. F., Jr (1991). Gonadotropin-releasing hormone and its analogues. The New England journal of medicine, 324(2), 93–103. https://doi.org/10.1056/NEJM199101103240205.
  8. Happ, J., Ditscheid, W., & Krause, U. (1985). Pulsatile gonadotropin-releasing hormone therapy in male patients with Kallmann's syndrome or constitutional delay of puberty. Fertility and sterility, 43(4), 599–608. https://doi.org/10.1016/s0015-0282(16)48504-3.
  9. Blumenfeld, Z., Makler, A., Frisch, L., & Brandes, J. M. (1988). Induction of spermatogenesis and fertility in hypogonadotropic azoospermic men by intravenous pulsatile gonadotropin-releasing hormone (GnRH). Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology, 2(2), 151–164. https://doi.org/10.3109/09513598809023623.
  10. Chen C-P, Lu X. Gonadotropin-releasing hormone receptor inhibits triple-negative breast cancer proliferation and metastasis. Journal of International Medical Research. 2022;50(3). doi:10.1177/03000605221082895.
  11. Huerta-Reyes, M., Maya-Núñez, G., Pérez-Solis, M. A., López-Muñoz, E., Guillén, N., Olivo-Marin, J. C., & Aguilar-Rojas, A. (2019). Treatment of Breast Cancer With Gonadotropin-Releasing Hormone Analogs. Frontiers in oncology, 9, 943. https://doi.org/10.3389/fonc.2019.00943.
  12. Chenault, J.R. et al. (2014) “Evaluation of gonadotropin-releasing hormone hydrogen chloride at 3 doses with prostaglandin F2Α for fixed-time artificial insemination in dairy cows,” Journal of Dairy Science, 97(5), pp. 2816–2821. Available at: https://doi.org/10.3168/jds.2013-7453.
  13. Chow, V.D.W. et al. (2000) “Intranasal gonadotropin-releasing hormone (GnRH) therapy for men with idiopathic infertility: Gnrh stimulation test may predict response to treatment,” Fertility and Sterility, 74(3), pp. 605–606. Available at: https://doi.org/10.1016/s0015-0282(00)00699-3.
  14. Happ, J. et al. (1975) “Intranasal GnRH therapy of maldescended testes,” Hormone and Metabolic Research, 7(05), pp. 440–441. Available at: https://doi.org/10.1055/s-0028-1095673.
  15. Kliesch, S., Behre, H. M., & Nieschlag, E. (1995). Recombinant human follicle-stimulating hormone and human chorionic gonadotropin for induction of spermatogenesis in a hypogonadotropic male. Fertility and sterility, 63(6), 1326–1328. https://doi.org/10.1016/s0015-0282(16)57619-5.
  16. Cote, D. J., Smith, T. R., Sandler, C. N., Gupta, T., Bale, T. A., Bi, W. L., Dunn, I. F., De Girolami, U., Woodmansee, W. W., Kaiser, U. B., & Laws, E. R., Jr (2016). Functional Gonadotroph Adenomas: Case Series and Report of Literature. Neurosurgery, 79(6), 823–831. https://doi.org/10.1227/NEU.0000000000001188.
  17. Iwamoto, H., Yoshida, A., Suzuki, H., Tanaka, M., Watanabe, N., & Nakamura, T. (2009). A man with hypogonadotropic hypogonadism successfully treated with nasal administration of the low-dose gonadotropin-releasing hormone analog buserelin. Fertility and sterility, 92(3), 1169.e1–1169.e3. https://doi.org/10.1016/j.fertnstert.2009.05.090.
  18. Surrey, E. S., & Hornstein, M. D. (2002). Prolonged GnRH agonist and add-back therapy for symptomatic endometriosis: long-term follow-up. Obstetrics and gynecology, 99(5 Pt 1), 709–719. https://doi.org/10.1016/s0029-7844(02)01945-2.
  19. Ying, W. (2008) “The nose may help the brain: Intranasal drug delivery for treating neurological diseases,” Future Neurology, 3(1), pp. 1–4. Available at: https://doi.org/10.2217/14796708.3.1.1.
  20. Julien, A.R. et al. (2019) “Nasal administration of gonadotropin releasing hormone (GnRH) elicits sperm production in Fowler’s Toads (Anaxyrus fowleri),” BMC Zoology, 4(1). Available at: https://doi.org/10.1186/s40850-019-0040-2.
  21. Goto, T. et al. (2003) “Single dose nasal spray of gonadotropin releasing hormone (GnRH) agonist effectively matures oocytes for in vitro fertilization in an ovarian stimulation protocol using clomiphene citrate, gonadotropin, and GnRH antagonist,” Fertility and Sterility, 80, p. 6. Available at: https://doi.org/10.1016/s0015-0282(03)01816-8.
  22. Rajfer, J. et al. (1986) “Comparison of the efficacy of subcutaneous and nasal spray buserelin treatment in suppression of testicular steroidogenesis in men with prostate cancer,” Fertility and Sterility, 46(1), pp. 104–110. Available at: https://doi.org/10.1016/s0015-0282(16)49466-5.
  23. Nielsen, D.S. et al. (2017) “Orally absorbed cyclic peptides,” Chemical Reviews, 117(12), pp. 8094–8128. Available at: https://doi.org/10.1021/acs.chemrev.6b00838.
  24. Han, Y. et al. (2019) “Multifunctional oral delivery systems for enhanced bioavailability of therapeutic peptides/proteins,” Acta Pharmaceutica Sinica B, 9(5), pp. 902–922. Available at: https://doi.org/10.1016/j.apsb.2019.01.004.
  25. Pitteloud, N. et al. (2002) “Predictors of outcome of long-term GnRH therapy in men with idiopathic hypogonadotropic hypogonadism,” The Journal of Clinical Endocrinology & Metabolism, 87(9), pp. 4128–4136. Available at: https://doi.org/10.1210/jc.2002-020518.
  26. Zhang, L. et al. (2018) “The pulsatile gonadorelin pump induces earlier spermatogenesis than cyclical gonadotropin therapy in congenital hypogonadotropic hypogonadism men,” American Journal of Men's Health, 13(1), p. 155798831881828. Available at: https://doi.org/10.1177/1557988318818280.

Scientifically Fact Checked by:

David Warmflash, M.D.

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