Tesamorelin Peptide: Benefits, side effects, dosage details, and how it works

You’ve probably encountered at least one prescription peptide ad without realizing it’s a peptide ad or even what a peptide is. But chances are that you recognize the names Ozempic, Wegovy, and even insulin. They’re all peptides.

Tesamorelin is also a peptide, but it belongs to a different class and has the potential to treat a host of concerns. Let’s take some time to learn what this powerful therapy can do to improve your health and quality of life.

Over the past two decades, Innerbody Research has helped tens of millions of readers make more informed decisions about staying healthy and living healthier lifestyles.

Everything we write is grounded in the available science on the subject. With tesamorelin and peptide therapies more broadly, we’ve spent over 200 hours digging in the literature and analyzing the findings to explore its promise as a valid treatment. As much as possible, we focused on direct clinical research on tesamorelin’s effects on visceral fat, muscle development, and cognition. When direct research was lacking, we examined the relevant biomechanisms — growth hormone, IGF-1 — to understand how increases in their production could affect human health and wellness. Our relationships with medical providers gave us a deeper understanding of the protocols and effects of tesamorelin based on their observations across years of practice, and we’ve folded that insight into this article to balance theory and real-world outcomes. One of our team members has also gained hands-on experience with tesamorelin in his ongoing peptide therapy.

Additionally, like all health-related content on this website, this guide was thoroughly vetted by one or more members of our Medical Review Board for accuracy and will continue to be monitored for updates by our editorial team.

Tesamorelin (a.k.a. tesamorelin acetate or TH9507) is a synthetic, therapeutic polypeptide analog.1 Let’s break down what that means.

• Synthetic: It was created in a laboratory.
• Therapeutic: It’s used to treat disease.
• Polypeptide: It’s a long chain of amino acids2 — 44, to be exact.
• Analog: It’s based on a naturally occurring peptide — in this case, growth hormone-releasing hormone (GHRH).

Therapeutic peptides generally work by binding to cellular surfaces and triggering effects within the cells. According to the authors of a 2022 review on the subject, the mode of action is “similar … to biologics.”3 In other words, they mimic the native chemicals on which they’re based.

GHRH, the chemical basis for tesamorelin, does what its name says. Produced in the hypothalamus, the brain’s control center for many bodily functions, it causes the pituitary gland to release growth hormone.4 5 Growth hormone, in turn, acts on almost every organ and tissue in two aspects:

Like most therapeutic peptides, tesamorelin comes as a powder that must be reconstituted into a solution. The exact instructions for reconstitution may vary, but they generally involve combining the powder with sterile water in a syringe.

Peptides are normally administered by subcutaneous injection, and so it goes with tesamorelin. It has a dosing frequency of 5-7 days per week. The monthly protocol may involve a cycle of regular dosing for 2-3 months straight, followed by a one-month break.

You might sometimes find tesamorelin as an oral medication (e.g., tablets or troches), but availability seems to fluctuate. In most cases, it’s an injectable.

Also, peptide therapy is usually an ongoing treatment. With tesamorelin, you see results only as long as you continue your injections.8

Because it acts on growth and metabolism, tesamorelin’s therapeutic uses apply most directly to building physical strength and shrinking visceral fat.

Abdominal obesity

In a 12-month clinical trial published in 2010, which involved 404 HIV-infected patients with excess abdominal fat, the group that received 2mg of tesamorelin per day saw an 18% decrease in visceral fat compared to placebo.9

There are two things to note in order to appreciate the full scope of these findings:

• Visceral fat (i.e., fat accumulation around the abdominal organs) is famously stubborn and can’t be burned selectively through exercise. This is the type of fat that contributes most severely to things like diabetes, heart disease, and stroke.10 Yet tesamorelin appears to target it specifically. The researchers behind the 2010 trial theorized its mechanism of action involves “some mild aggravation of insulin,” high amounts of which correspond with visceral fat accumulation.9 11
• HIV and certain HIV treatments seem to facilitate the accumulation of visceral fat.12 It isn’t clear why. In any case, people with HIV are among the best-studied subjects for tesamorelin’s efficacy for fat loss.

Here, you can see, we’re talking about a hard-to-lose type of fat and mysterious circumstances of onset, but tesamorelin seems to work nonetheless. And although research on people without HIV is minimal to nonexistent at this time, researchers believe tesamorelin can yield similar outcomes in non-HIV populations.13

But if you’re thinking it’s an alternative to a weight loss therapy like Ozempic, you should know that tesamorelin has demonstrated no effect on subcutaneous fat — the fat that most people associate with overweight and obesity. Moreover, visceral fat is likely to return in anyone who discontinues their tesamorelin therapy, whereas patients who’ve taken semaglutide (e.g., Ozempic) have seen at least some longer-lasting health outcomes after ending their treatment.14 29

Therefore, there are three takeaways about tesamorelin and abdominal fat:

1. Tesamorelin may be able to reduce your morbidity for serious chronic health conditions.
2. This peptide probably isn’t the treatment you want for cosmetic weight loss.
3. If you start tesamorelin therapy, you should expect to make it an ongoing commitment.

Muscle wasting, poor muscle tone, and weakness

As a therapy for people with HIV, tesamorelin plays double duty as a countermeasure against another common symptom of the disease: wasting.15 Defined in part as the loss of more than 10% of a person’s body weight, HIV-associated wasting is thought to stem from various aspects of HIV infection and treatment — low appetite, altered metabolism, poor nutrient absorption, opportunistic infections, depression, drug side effects, and inflammation.16 It’s a serious consequence but one that can be mitigated.

Tesamorelin can help with mitigation because it stimulates growth hormone secretion. Its utility toward this end was the subject of a 2020 analysis of two clinical trials on individuals with HIV in which the authors concluded, “Tesamorelin was effective in increasing skeletal muscle area and density.”17

Strength and muscle studies are lacking with regard to non-HIV subjects, but the theoretical efficacy is there. Consider a 2006 study on Japanese patients with growth hormone deficiency, in which growth hormone replacement therapy resulted in “significantly improved body composition.”18

As you might expect, given its most common therapeutic uses, tesamorelin imparts noticeable benefits in terms of lipid profiles and muscle mass. Studies have demonstrated not only visceral fat loss, increased skeletal muscle, and improved body composition,9 17 18 but also elevated secretions of growth hormone and IGF-1.19

But when the body experiences changes in one area of function, it can have a cascading effect on other areas as well. That’s why tesamorelin may provide additional benefits in:

In addition, according to the medical providers who’ve shared their observations with us, patients on tesamorelin may also see improvements in energy, physical strength, metabolism, hormonal balance, and markers of nonalcoholic fatty liver disease.

Tesamorelin generally has a low safety risk partly because it’s a prescription-only treatment. Prescribing physicians usually require initial and ongoing biomarker testing to ensure a candidate’s suitability.

The existing literature also indicates that tesamorelin is largely safe for use among people with indicated health concerns, such as excessive abdominal fat and muscle wasting. For example, in a study we referenced earlier, which entailed 52 weeks of tesamorelin administration in patients with HIV, the researchers found the peptide to be “generally well tolerated.” Importantly, tesamorelin caused no significant elevations in glucose, which would have represented a severe safety hazard given the relationship between hyperglycemia and diabetes.9 26

That being said, there are contraindications and potential side effects:

Research-grade vs. pharmaceutical-grade tesamorelin

When you’re shopping for tesamorelin online, you might come across options listed as “research-grade,” “laboratory-grade,” or “reagent-grade.” That means the tesamorelin is intended for laboratory use only — so that trained professionals can study its structure and effects. It has not been stringently monitored for contaminants that can harm the user, so it is potentially unsafe and not to be used as a therapeutic drug.

What you should look for is something labeled “pharmaceutical-grade” or “GMP API” (good manufacturing practices for active pharmaceutical ingredients).32 Tesamorelin labeled as such has been approved by the Food & Drug Administration for human use.33

The tesamorelin experience can vary to certain degrees, but new patients can expect some commonalities in terms of the treatment protocol. Here, we take you through its various aspects:

Biomarker testing

If you’re a candidate for tesamorelin, your doctor will order lab tests to analyze biomarkers related to pertinent health conditions. Biomarker testing will also take place periodically throughout your treatment so that your doctor can assess your response to the medicine.30

Dosing and administration

A tesamorelin dose is usually 1-2mg by subcutaneous injection, the dosing frequency is either five or seven days a week, and each day’s dose normally occurs in the evening to coincide with the body’s natural growth hormone release pattern.28

Each dose is self-administered. Your prescribing physician will likely give you a handout detailing the process, as well as a kit that includes a vial of tesamorelin powder, a vial of bacteriostatic water, alcohol swabs, and needle syringes.

You’ll be responsible for reconstituting the tesamorelin powder with the bacteriostatic water. To do so, you:

• Sterilize the vials with an alcohol swab to prevent pathogenic transmission
• Inject the needle syringe into the bacteriostatic water vial and draw out the amount indicated by your prescriber
• Inject the water-filled syringe into the tesamorelin vial and slowly introduce the water to the powder
• Remove the syringe
• Gently swirl to dissolve the powder into a solution (don’t shake to mix, which can degrade the peptide and create foam)
• Reinsert the syringe into the tesamorelin vial and draw out the prescribed volume of solution
• Sterilize the injection site — an area of subcutaneous fat in the belly, thigh, or arm
• Poke the syringe needle into the injection site and depress the plunger
• Dispose of the used syringe

Tesamorelin often comes in a large vial meant to be used throughout the month, in which case reconstitution is necessary only once per shipment, not per dose. However, some tesamorelin comes in single-use vials, which require daily reconstitution.

Storage

As long as you aren’t using single-use vials, a shipment’s worth of tesamorelin should last four weeks. The remainder must be stored in the refrigerator, ideally between 36 and 46 degrees Fahrenheit (2-8 degrees Celsius).31 The other kit items — bacteriostatic water, alcohol swabs, and needle syringes — can be kept at room temperature. You shouldn’t have to worry about the medicine becoming contaminated while in storage. Medical vials often have self-healing rubber stoppers on top. The stoppers have elastic properties that allow them to “close” the puncture you make with the needle when you insert or draw out the contents. If your vials don’t have rubber stoppers, you’ll want to ask your prescriber about the ideal storage protocol.

Treatment cycle and timeline of effects

Treatment may follow a cycle. A normal cycle lasts 3-4 months — that’s 2-3 months on, followed by one month off. Treatment is ongoing, so a year comprises 3-4 cycles.

Therapeutic effects tend to follow a schedule, too. Based on what we’ve learned from our interactions with treatment providers, we’d say an ordinary tesamorelin treatment timeline looks like this:

• Within 1-2 weeks, you should begin to experience reductions in your visceral fat.
• At 4-6 weeks, your abdominal fat should begin to reduce significantly, and your lipid profiles ought to improve. Improvements in muscle mass are often seen at this point as well.
• By 8-12 weeks, the full benefits of treatment should become evident: substantial visceral fat reduction, better body composition, and enhanced cognitive function.

Thereafter, it’s mostly about maintaining your protocol and health outcomes, but you should also start to see improvements in cardiovascular health along with positive changes in physical performance attendant with your changing body composition.

Tesamorelin is approved as a therapy for patients with HIV who’ve accumulated excess abdominal fat, but it is also prescribed off-label to people seeking reductions in their visceral adiposity, increases in their muscle mass, and improvements in their cardiovascular or cognitive health. In some cases, treatment is indicated for individuals seeking cosmetic improvements in their skin health.

More specifically, you may be a candidate for tesamorelin if you (a) don’t have a contraindicated health condition and (b) are at risk of one or more of the following:

Clinics have been prescribing peptides to private clients for years, and telehealth is only just catching up. Even among the reputable telehealth providers that are riding the peptide wave, the selection is usually limited to GLP-1 receptor agonists like Ozempic, Wegovy, and Mounjaro. Tesamorelin, however, isn’t a GLP-1 RA and currently isn’t offered by many leading telehealth platforms such as Hims, Hers, Eden, Henry Meds, or Strut.

Right now, the best way to get a tesamorelin prescription is through a local medical provider.

Because the telehealth space is playing catch-up, less-reputable outfits have seen an opportunity to capitalize on the growing public interest in peptide therapy. That’s why you can still find a few online purveyors that carry tesamorelin, and it’s tough to say whether or not a given one is trustworthy.

Often, you’ll find that they sell research-grade tesamorelin, which is intended only for laboratory use. If you were to inject research-grade tesamorelin into your body, you run the risk of introducing contaminants that could cause serious harm. Legitimate online peptide purveyors will deal exclusively in products labeled “pharmaceutical-grade” or “GMP API,” which indicates FDA approval for human use.

However, among the few online providers that offer tesamorelin, none of them appear to be well-represented on the major consumer watchdog sites. They tend to have only a handful of reviews, and that’s hardly enough to feel confident about the honesty of their labeling or the quality of their products. Again, we’re not saying one or another operation is not legit, only that we can’t confidently make an accurate assessment at this time.