Last Updated February 26, 2024

 February 26, 2024

Curious about tesamorelin vs. ipamorelin — and how these two research peptides compare?

Many researchers in the growth hormone therapy field are interested in the similarities and differences between tesamorelin and ipamorelin. Both of these peptides increase the synthesis and release of endogenous human growth hormone.

But they're slightly different in how they work, as well as in their potential benefits and side effects.

Tesamorelin is an FDA-approved treatment for reducing abdominal fat in HIV-infected patients with lipodystrophy, while ipamorelin has yet to complete human clinical trials and is typically administered in conjunction with a GHRH like tesamorelin or CJC-1295.

In this guide, we’ll detail the similarities and differences between the two peptides to help interested researchers decide which peptide merits further investigation.

Disclaimer: contains information about products that are intended for laboratory and research use only, unless otherwise explicitly stated. This information, including any referenced scientific or clinical research, is made available for educational purposes only. Likewise, any published information relative to the dosing and administration of reference materials is made available strictly for reference and shall not be construed to encourage the self-administration or any human use of said reference materials. makes every effort to ensure that any information it shares complies with national and international standards for clinical trial information and is committed to the timely disclosure of the design and results of all interventional clinical studies for innovative treatments publicly available or that may be made available. However, research is not considered conclusive. makes no claims that any products referenced can cure, treat or prevent any conditions, including any conditions referenced on its website or in print materials.

What are Research Peptides?

Research peptides, known as peptide drug products, are at the forefront of ongoing GH therapy research and experimentation [1]. They're essentially chains of molecules called amino acids — the same molecules that make up proteins. Peptides naturally occur in the body or can be synthesized in laboratory settings via chemical synthesis.

According to the United States Food & Drug Administration (FDA), any polymer composed of 40 or fewer amino acids can be considered to be a peptide. To date, there are over 100 peptide drug products marketed in the U.S., Europe and Japan — in a global market estimated to be worth over $20 billion [2].

Because peptide drug products are so promising, many scientists and researchers are eager to conduct further research. There are currently almost 500 peptides recognized by the FDA as having therapeutic value to potentially treat various diseases, including [3]:

  • Bone disorders
  • Genetic disorders
  • Cancer
  • Infectious disease
  • Cardiovascular problems
  • Immune system
  • Respiratory disorders
  • Eye disorders
  • Neurodegenerative problems
  • Poor hormonal health
  • Bone disorders

Some of the most commonly used GHRH-promoting peptide drug products include tesamorelin, ipamorelin and sermorelin. In the following section, we will take a closer look at tesamorelin.

tesamorelin vs ipamorelin

What is Tesamorelin?

Tesamorelin is a synthetic GHRH analogue that was created in the 1990s by the Canadian technology company Theratechnologies [4]. It has been approved by the FDA to treat visceral adiposity (excessive fat around the midsection) in HIV-infected patients with lipodystrophy [5]. For this exclusive purpose, it is sold under the trade name EGRIFTA.

Mechanism of Action

The chemical structure of tesamorelin is almost identical to the hypothalamic peptide “growth hormone-releasing hormone” (GHRH), which occurs naturally in the body. This hormone plays a role in regulating the synthesis and release of human growth hormone (HGH).

Tesamorelin works by binding to receptors in the pituitary gland, and stimulating the gland to produce and release even more HGH. The result is an increase in the concentration of HGH in the blood [6]. By up-regulating the amount of HGH in the bloodstream, tesamorelin offers several research-backed benefits.

Benefits of Tesamorelin

Tesamorelin's main clinical benefit is that it helps treat HIV-positive patients who suffer from lipodystrophy, a condition that leads to excessive visceral adipose tissue (VAT) around the trunk. Tesamorelin has been shown to decrease VAT and help decrease the waist circumference of adults with HIV [6].

In other clinical trials involving HIV-infected adults, tesamorelin has been shown to help decrease muscle fat while simultaneously increasing muscle area [7] and lowering levels of overall abdominal fat [8] caused by long-term antiretroviral therapy. Tesamorelin therapy has been shown to trigger lipolysis, or fat burning, especially around the abdominal area [9].

To date, the only tesamorelin research conducted on adults without HIV involved measuring levels of neurotransmitters in the brain. A Washington state study found that tesamorelin helps lower levels of myo-inositol (MI), an osmolyte linked to early-onset Alzheimer's disease [10]. In the next section, ipamorelin will be introduced and discussed.

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What is Ipamorelin?

Ipamorelin is a pentapeptide that was developed by Novo Nordisk, a Danish pharmaceutical company. Ipamorelin is composed of a chain of five amino acids, making it much simpler than tesamorelin. It is chemically very similar to the body's own natural growth hormone-releasing peptide (GHRP)-1, with the main difference being that it lacks the central dipeptide Ala-Trp found in GHRP-1 [11].

Unlike tesamorelin, ipamorelin has not been approved by the FDA for any use, and has yet to be reviewed in human clinical trials. All data related to ipamorelin's efficacy, benefits, and safety is from animal studies.

Mechanisms of Action

Like tesamorelin, ipamorelin is a GH secretagogue, meaning that it promotes the synthesis and release of GH in vitro and in vivo. Animal studies have shown that ipamorelin is able to bind to primary rat pituitary cells and stimulate the release of GH into the blood. It binds to cells in the pituitary gland, prompting the release of additional HGH into the bloodstream [11].

The other effect of ipamorelin is to suppress somatostatin, which is a hormone that inhibits the production of HGH. By reducing this HGH inhibitor, ipamorelin indirectly increases the body's ability to produce additional HGH.

Benefits of Ipamorelin

Similar to tesamorelin, the main benefit of ipamorelin is that it appears to increase HGH levels. Based on research data, composed of animal studies, the following is worth noting:

  • The results of animal studies indicate that ipamorelin appears to be a “selective” GH secretagogue. This means it only up-regulates HGH, but not other hormones like cortisol or adrenocorticotropic hormone (ACTH) [11].
  • In a study involving young female rats, ipamorelin was shown to help increase “body weight gain” and enhance “in vitro basal and ipamorelin or GHRH-stimulated GH release” [12].
  • A study involving groups of 8-month-old female rats found that ipamorelin could “counteract the catabolic effects of glucocorticoid (GC) on skeletal muscles and bone” [13].
    Ipamorelin has been shown to induce longitudinal bone growth in rats [14].

Following this review of the benefits of ipamorelin, we can now discuss whether researchers should investigate tesamorelin or ipamorelin as their HGHR peptide of choice.

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Best Human Growth Hormone-Releasing Peptide?

The studies cited above have confirmed that both tesamorelin and ipamorelin appear to offer similar benefits, but which one is superior from a research standpoint?

A key difference between these peptides is that while they both appear to increase the secretion and production of HGH in vitro and in vivo, only tesamorelin has undergone human clinical trials and has been approved by the FDA.

Another key difference between these two peptides is that ipamorelin does not adversely affect ACTH or cortisol, at least not based on the rat and swine studies [11].

In the following section, we will discuss the differences between tesamorelin and ipamorelin in greater detail.

Differences Between Tesamorelin and Ipamorelin

While there are strong similarities between tesamorelin and ipamorelin, researchers will note that these peptides differ significantly in the following ways.

The primary difference between ipamorelin vs. tesamorelin is chemical.

They are both peptides, thus short chains of amino acids. But tesamorelin is much longer at 44 amino acids in length. By contrast, ipamorelin is made up of just five amino acids.

Mechanism of Action

The structural difference between tesamorelin and ipamorelin means that the two have a slightly different mechanism of action. Tesamorelin is a stabilized peptide analogue of growth hormone-releasing hormone (GHRH) while ipamorelin is a growth hormone-releasing secretagogue. They mimic slightly different chemicals in the body and bind to different receptors.

So while they have the same ultimate effect of increasing HGH, they do so in slightly different ways. Tesamorelin is an FDA-approved treatment for reducing excess abdominal fat in HIV-infected patients with lipodystrophy and may be administered as a standalone treatment. Ipamorelin, on the other hand, has yet to pass human clinical trials and is typically administered in conjunction with another peptide.

Ipamorelin vs. Tesamorelin Cost

Another key difference between ipamorelin and tesamorelin is cost.

How much does ipamorelin cost? Ipamorelin costs about $50 for 5 mg while tesamorelin costs about $70 for 5 mg. Depending on the dosing protocol adopted by the researcher, ipamorelin may cost significantly less than tesamorelin.

How Are Tesamorelin and Ipamorelin Dosed?

This section will outline how tesamorelin and ipamorelin are typically dosed and cycled in research-only settings:

Tesamorelin Dosage and Administration

The recommended dose of tesamorelin (EGRIFTA™) for HIV-positive adult patients with lipodystrophy is 2 mg injected subcutaneously once daily [15].

In the clinical context, patients are typically instructed to follow this dosing schedule:

  • One subcutaneous injection containing 2 mg tesamorelin daily
  • Taken at the same time each day, ideally before bed
  • Five days per week
  • Continue for 60 days, with one month off

Ipamorelin Dosage and Administration

In terms of ipamorelin dosage, this peptide has not been approved for human use and therefore has no “recommended” dosage or cycling structure. Ipamorelin was investigated in phase II clinical trials for the treatment of postoperative ileus; however, these trials were discontinued due to lack of efficacy [16].

Participants in this small proof of concept study were given intravenous infusions of 0.03-mg/kg ipamorelin twice daily for 7 days after undergoing small and large bowel resection by open or laparoscopic surgery. The study found that “ipamorelin 0.03-mg/kg twice daily for up to 7 days was well tolerated” [16]. There is clearly potential for further research in terms of ipamorelin’s long-term safety and effects.

There is strong research interest in the application of both tesamorelin and ipamorelin to improve both body composition and physical performance. However, there are no official or published figures to indicate the dosage at which either peptide should be administered to these ends [17].

However, a WADA-funded study into the effects of growth hormone (GH) on athletic performance gives some insight into how peptides may be administered. In the study, recreational athleted were administered GH at a dose of 2 mg injected subcutaneously once daily [18].

This offers some indication of how GH may be supplemented to increase physical performance and how ipamorelin may be administered at a lower dose in conjunction with a GHRH like tesamorelin or CJC-1295.

tesamorelin vs ipamorelin

Where to Buy Research Peptides Online? | 2024 Edition

Researchers interested in identifying a trustworthy tesamorelin and ipamorelin vendor are well-advised to consider questions like:

  • Does the vendor publish certificates of analysis that back their products’ quality and purity?
  • Are there independent reviews of the vendor on trusted third-party websites?
  • Can researchers use secure payment methods?
  • Is reasonably priced shipping available?

We recommend the following two vendors of tesamorelin and ipamorelin based on several successful orders.

Limitless Life

We've had only excellent experiences with Limitless Life and can vouch for their high-quality peptides.

Here's why we consistently choose to shop with this vendor:

  • USA Made & Lab-Tested Peptides: All Limitless Life peptides are synthesized in accredited American facilities and then undergo third-party quality testing to ensure suitability for research use.
  • Secure Payments: Checkout is a breeze over at Limitless Life, as the vendor accepts major credit cards, e-checks, cryptocurrencies and even CashApp among its payment methods.
  • Smooth Shipping: The vendor offers convenient shipping options with quick delivery, and even waives the low standard fee on orders of $350+.

Tesamorelin from Limitless Life is available to customers who register for the vendor’s VIP peptide club.

Ipamorelin from Limitless Life may be purchased through the vendor’s main site. Use coupon code peptidesorg10 to get 10% off.

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Xcel Peptides

Xcel Peptides is a newer vendor that also carries research-grade tesamorelin and ipamorelin at reasonable prices, offering additional benefits like:

  • Lab-Tested Compounds: All Xcel Peptides comounds are tested by the analytical laboratory Janoshik, with the corresponding Cerficates of Analysis posted directly on the vendor’s website.
  • Quick Checkout: Xcel Peptides has a streamlined checkout procedure in place and supports many payment methods like credit cards, Zelle, Venmo, and Cash App.
  • Fast Support: Xcel Peptides’ service team is always on top of things and is reachable by phone and email during standard business hours.

Be sure to get a further 10% off from Xcel Peptides by signing up to their informative email newsletter!

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Side Effects and Safety Concerns

So both tesamorelin and ipamorelin appear to be effective at promoting GH in the body. But are they safe? What are the side effects of ipamorelin and tesamorelin?

The short answer is that only tesamorelin has undergone human clinical trials and has received FDA approval for an extremely limited purpose. Ipamorelin studies are lacking overall and this merits further research.

Here’s what we know.

Tesamorelin Side Effects

Tesamorelin has only been studied in HIV-positive adults. Results show that the most common side effects are:

  • Sweating
  • Redness, itching, pain, swelling, and irritation at the site of injection
  • Diarrhea
  • Muscle aches

Additionally, tesamorelin has been linked to glucose intolerance and found to increase the risk of type 2 diabetes mellitus. The drug is contraindicated during pregnancy [4].

Ipamorelin Side Effects

As ipamorelin has not been approved for human use, ipamorelin side effects require further research. As a GHRH secretagogue that is subcutaneously injected, ipamorelin likely causes side effects related to frequent injections such as pain, rash or soreness at injection sites, in common with other forms of GH therapies [19].

Avoiding Side Effects

Researchers who are new to working with peptides are advised to screen test subjects for pre-existing conditions and follow approved protocols to minimize the risk of injection-related complications.

Bacteriostatic Water for Research Peptides

To meet the leading standards in peptide research, labs must have the recommended tools on hand. For example, when properly handling Tesamorelin, researchers will need items such as sterile vials and bacteriostatic water to safely prepare and store the solution.

Taking the time to gather all the necessary supplies can be an arduous task for many researchers.

For this reason, the team has searched the web to find the top supplier of research materials — right here.

Ipamorelin vs. Tesamorelin | Verdict

Between tesamorelin and ipamorelin, which ultimately wins out?

From an experimental standpoint, tesamorelin has the clear advantage of having been evaluated in human clinical trials and approved by the FDA for use in humans. It still presents many avenues for further research, such as long-term cardiovascular benefits and safety.

By comparison, ipamorelin has yet to receive FDA approval and remains a research peptide that is typically taken with a GHRH receptor agonist like tesamorelin itself or CJC-1295.

For qualified researchers looking to source peptides, please visit our top-rated supplier.


  1. Lee, Andy Chi-Lung et al. “A Comprehensive Review on Current Advances in Peptide Drug Development and Design.” International journal of molecular sciences vol. 20,10 2383. 14 May. 2019, doi:10.3390/ijms20102383
  2. Food and Drug Administration (2020). Impact Story: Developing the Tools to Evaluate Complex Drug Products: Peptides. Retrieved March 28, 2020.
  3. THPdb: A database of FDA approved therapeutic peptides and proteins. Retrieved March 27, 2020.
  4. Patel, A., Gandhi, H., & Upaganlawar, A. (2011). Tesamorelin: A hope for ART-induced lipodystrophy. Journal of Pharmacy And Bioallied Sciences, 3(2), 319.
  5. LiverTox: Clinical and Research Information on Drug-Induced Liver Injury [Internet]. Bethesda (MD): National Institute of Diabetes and Digestive and Kidney Diseases; 2012–. Tesamorelin. 2018 Oct 20. PMID: 31644039.
  6. Spooner LM, Olin JL. Tesamorelin: a growth hormone-releasing factor analogue for HIV-associated lipodystrophy. Ann Pharmacother. 2012 Feb;46(2):240-7. doi: 10.1345/aph.1Q629. Epub 2012 Jan 31. PMID: 222986
  7. Adrian, S., Scherzinger, A., Sanyal, A. et al. The Growth Hormone Releasing Hormone Analogue, Tesamorelin, Decreases Muscle Fat and Increases Muscle Area in Adults with HIV. J Frailty Aging 8, 154–159 (2019).
  8. Dhillon, S. Tesamorelin. Drugs 71, 1071–1091 (2011).
  9. Clinical Review Report: Tesamorelin (Egrifta) [Internet]. Ottawa (ON): Canadian Agency for Drugs and Technologies in Health; 2016 Aug. Executive Summary. Available from:
  10. Friedman SD, Baker LD, Borson S, et al. Growth Hormone–Releasing Hormone Effects on Brain γ-Aminobutyric Acid Levels in Mild Cognitive Impairment and Healthy Aging. JAMA Neurol. 2013;70(7):883–890. doi:10.1001/jamaneurol.2013.1425
  11. Raun K, Hansen BS, Johansen NL, Thøgersen H, Madsen K, Ankersen M, Andersen PH. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol. 1998 Nov;139(5):552-61. doi: 10.1530/eje.0.1390552. PMID: 9849822.
  12. Jiménez-Reina, L., Cañete, R., De la Torre, M. J., & Bernal, G. (2002). Chronic in vivo Ipamorelin treatment stimulates body weight gain and growth hormone (GH) release in vitro in young female rats. European Journal of Anatomy, 6(1), 37-45.
  13. Andersen, N. B., Malmlöf, K., Johansen, P. B., Andreassen, T. T., Ørtoft, G., & Oxlund, H. (2001). The growth hormone secretagogue ipamorelin counteracts glucocorticoid-induced decrease in bone formation of adult rats. Growth Hormone & IGF Research, 11(5), 266-272.
  14. Johansen PB, Nowak J, Skjaerbaek C, Flyvbjerg A, Andreassen TT, Wilken M, Orskov H. Ipamorelin, a new growth-hormone-releasing peptide, induces longitudinal bone growth in rats. Growth Horm IGF Res. 1999 Apr;9(2):106-13. doi: 10.1054/ghir.1999.9998. PMID: 10373343.
  15. (2021). Retrieved 29 May 2021, from
  16. Beck, D.E., Sweeney, W.B., McCarter, M.D. et al. Prospective, randomized, controlled, proof-of-concept study of the Ghrelin mimetic ipamorelin for the management of postoperative ileus in bowel resection patients. Int J Colorectal Dis 29, 1527–1534 (2014).
  17. Erotokritou-Mulligan, Ioulietta et al. “Growth hormone doping: a review.” Open access journal of sports medicine vol. 2 99-111. 27 Jul. 2011, doi:10.2147/OAJSM.S11626
  18. Meinhardt U, Nelson AE, Hansen JL, Birzniece V, Clifford D, Leung KC, Graham K, Ho KK. The effects of growth hormone on body composition and physical performance in recreational athletes: a randomized trial. Ann Intern Med. 2010 May 4;152(9):568-77. doi: 10.7326/0003-4819-152-9-201005040-00007. PMID: 20439575.
  19. Souza, F. M., & Collett-Solberg, P. F. (2011). Adverse effects of growth hormone replacement therapy in children. Arquivos Brasileiros De Endocrinologia & Metabologia, 55(8), 559-565.

Scientifically Fact Checked by:

David Warmflash, M.D.

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