iPamorelin is a known as a Growth Hormone Releasing Peptide (GHRP) and a Ghrelin Mimetic as it mimics ghrelin and binds to the ghrelin receptor in the brain, therefore stimulating the release of Human Growth Hormone (HGH) from the pituitary gland.

Research has shown that Ipamorelin is both highly potent and very selective compared to other GHRPs, such as GHRP-6 and GHRP-2. Furthermore, it doesn’t affect levels of the stress hormone Adrenocorticotropic (ACTH) and Cortisol, even at extreme doses. [1]

Cortisol Molecule
Cortisol Molecule

iPamorelin’s Benefits include;

  • Increased Production of *Growth Hormone (GH)
  • Improved Athletic Performance
  • Increased IGF-1 Production
  • Increases Lean Muscle Mass
  • Decreased Body Fat

iPamorelin History

Pituitary Gland
Pituitary Gland

iPamorelin was originally developed by Danish Pharmaceutical company Novo Nordisk and belongs to the 3rd generation of Growth Hormone Releasing Peptides that are designed to suppress the hormone somatostatin enabling the stimulation and release of GH from the pituitary gland.

Somatostatin plays an important role in balancing hormone levels in the body, in particular, regulating hormones released by the pituitary gland such as GH and prevent their over-production of other hormones such as insulin.

iPamorelin is one of the longest lasting GH peptides as it has a more natural steady GH release compared to other peptides which give an instant spike followed by a rapid falloff point.

iPamorelin Benefits

The benefits for any athlete using iPamorelin is due to its’ ability to stimulate GH production.

Growth Hormone (also known as Somatropin) was originally developed in the 1950s to treat dwarfism in children, and the consisted of extracts of the raw hormone from the pituitary of cadavers. This is known as cadaver-GH.

Then in 1966, Chinese born American Biochemist Choh Hao Li discovered that human growth hormone consists of a chain of 256 amino acids. By 1970 he succeeded in synthesising it.

3D Image of Growth Hormone
3D Image of Growth Hormone

However, in 1985, four cases of fatal degenerative brain disorder Creutzfeldt-Jakob Disease (CJD) or what is commonly known today as “mad cow disease.” were diagnosed in those who had been treated with cadaver-GH in the 1960s.

Following this discovery, the use of cadaver-GH to treat dwarfism quickly ceased.

It wasn’t until 1981 that American Pharmaceutical company Genentech pioneered the first use of recombinant human growth hormone to replace cadaver-GH.

The most famous study on Growth Hormone was conducted by Endocrinologist and Nutritionist, Dr Daniel Rudman, who showed that GH could reverse ageing by 10-15 years. The results which were published in the New England Journal of Medicine in 1990 found that volunteers aged 61 to 81 who received six months of GH injections presented with better results regarding bone density, lean muscle mass and reversal of fat decline. [2]

Growth Hormone is secreted in a pulsatile fashion and is stimulated by exercise, nutrition and sleep. Experts estimate that as much as 75 per cent of GH is released during sleep. [3]

In particular, GH affects a set of neurons in the brain called Orexins, which were only discovered in the 1990’s. Orexins have been scientifically shown to regulate the sleep/wake cycle by interacting with GABAergic sleep-promoting neurons and neurotransmitters like histamine, serotonin, melatonin, and acetylcholine. [4]

Neurons in the Brain
Neurons in the Brain

GABA (gamma-aminobutyric acid) is one of the key brain neurotransmitters and is a potent stimulator of GH-release. GABA release inhibits Orexins, as their main function is to create an awakened state. Research has found that after 20 weeks of GHRH administration, GABA levels were increased in the brain, which has a positive effect on sleep and therefore GH production. [5]

Research has also shown that even small changes in how orexins communicate with other areas of the brain during sleep can have a significant effect on waking times and the transition between the different stages of sleep. [6]

Furthermore, research has shown that there are bigger spikes in GH secretion during afternoon naps, compared to morning naps. [7]

Research has shown that has a positive effect on natural GH production in the body. This gives athletes the ability along with a good training and diet protocol to increase lean muscle mass, reduce body fat, and recover quicker from intense sessions and injuries.  [1]


When it comes to exercise research shows that the time of day does not alter the GH response to training. [8]

High Intensity Cardio

However, intensity can impact GH response. Research has shown that high-intensity exercise, such as HIIT, for a minimum of 10 minutes elicits the biggest stimulus to the secretion of GH. [9]


Growth Hormone works in conjunction with other hormones to keep you in optimal health.

Elevated levels of cortisol, glucose and even GH itself decrease GH production and secretion.

This is why fasting is a great stimulus for GH production. Research has shown that during fasting there is an GH spike early in the morning, but there is natural secretion throughout the day as well. The study at The University of Virginia showed a 5-fold increase in GH in response to a two day fast. [10]

iPamorelin Side effects

IPamorelin is one of the friendliest growth hormone supplements on the market, with any possible side effects happening during the early stages of use, these include;

  • Light Headed (diet adjustments may help)
  • Headaches (diet adjustments may help)
  • Sore injected area (injection rotation and finding new areas to inject may help)

Injection Site

It is recommended to lower your dose to find a suitable level if you experience any of the above symptoms.

iPamorelin Dosage

**Popularly Recommended Dosing Guidelines for iPamorelin

The recommended dosage is in the range of 200-300 mcg, 2-3 times per day. Always start with the lower dose and frequency and increase accordingly depending on results.

Final Thoughts

Compared to steroids and testosterone, which offer users a faster burn regarding results, peptides like iPamorelin offers more of a medium burn, though without the potentially uncomfortable side effects that come with the former. This is why if your goal is to increase muscle mass, burn body fat, and improve muscle recovery then peptides are the best option.

Older Bodybuilder

Disclaimer: Peptide Hormones are banned by WADA and most other global sporting organisation for both in-competition and out-of-competition use. You should NOT use them if you are competing in any such sanctioned sport as it a prohibited class of anabolic agents. Please check with local doping agencies for the latest information.

*Human Growth Hormone (HGH) and Growth Hormone (GH) are synonyms for the purpose of this article

**Popularly Recommended Dosing Guidelines are based on study and manufacturer information and are for informational purposes only.  Always consult a doctor and follow manufacturer recommendations when taking any supplement.


  1. Raun K1, Hansen BS, Johansen NL, Thøgersen H, Madsen K, Ankersen M, Andersen PH. Ipamorelin, the first selective growth hormone secretagogue. https://www.ncbi.nlm.nih.gov/pubmed/9849822 Accessed on 19 September 2018
  2. Daniel Rudman, M.D., Axel G. Feller, M.D., Hoskote S. Nagraj, M.D., Gregory A. Gergans, M.D., Pardee Y. Lalitha, M.D., Allen F. Goldberg, D.D.S., Robert A. Schlenker, Ph.D., Lester Cohn, M.D., Inge W. Rudman, B.S., and Dale E. Mattson, D. Effects of Human Growth Hormone in Men over 60 Years Old https://www.nejm.org/doi/full/10.1056/NEJM199007053230101?query=recirc_curatedRelated_article Accessed on 12 September 2018
  3. Godfrey RJ1, Madgwick Z, Whyte GP. The exercise-induced growth hormone response in athletes. https://www.ncbi.nlm.nih.gov/pubmed/12797841 Accessed on 12 September 2018
  4. López M1, Nogueiras R, Tena-Sempere M, Diéguez C. Orexins (hypocretins) actions on the GHRH/somatostatin-GH axis. https://www.ncbi.nlm.nih.gov/pubmed/19769635 Accessed on 12 September 2018
  5. Seth D. Friedman, PhD, Dr. Laura D. Baker, PhD, Dr. Soo Borson, MD, Dr. J. Eric Jensen, PhD, Ms. Suzanne M. Barsness, RN, MSN, Dr. Suzanne Craft, PhD, Dr. George R. Merriam, MD, Dr. Randolph K. Otto, MD, Dr. Edward J. Novotny, MD, and Dr. Michael V. Vitiello, PhD Growth Hormone–Releasing Hormone Effects on Brain γ-Aminobutyric Acid Levels in Mild Cognitive Impairment and Healthy Aging https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3764915/ Accessed on 12 September 2018
  6. Rupesh Kumar, Amitabha Bose, Birendra Nath Mallick A Mathematical Model towards Understanding the Mechanism of Neuronal Regulation of Wake-NREMS-REMS States https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0042059 Accessed on 12 September 2018
  7. Karacan I, Rosenbloom AL, Londono JH, Williams RL, Salis PJ. Growth hormone levels during morning and afternoon naps. https://www.ncbi.nlm.nih.gov/pubmed/4377652 Accessed on 12 September 2018
  8. Jill A. Kanaley Judy Y. Weltman  Karen S. Pieper  Arthur Weltman  Mark L. Hartman Cortisol and Growth Hormone Responses to Exercise at Different Times of Day https://academic.oup.com/jcem/article/86/6/2881/2849394 Accessed on 12 September 2018
  9. Godfrey RJ1, Madgwick Z, Whyte GP. The exercise-induced growth hormone response in athletes. https://www.ncbi.nlm.nih.gov/pubmed/12797841 Accessed on 12 September 2018
  10. Hartman ML1, Veldhuis JD, Johnson ML, Lee MM, Alberti KG, Samojlik E, Thorner MO. Augmented growth hormone (GH) secretory burst frequency and amplitude mediate enhanced GH secretion during a two-day fast in normal men. https://www.ncbi.nlm.nih.gov/pubmed/1548337 Accessed on 12 September 2018

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