Last updated 2026-07-24
TL;DR
Tesamorelin (brand name Egrifta) is FDA-approved as a 1mg or 2mg subcutaneous injection once daily, self-administered into the abdomen at bedtime, after reconstituting the lyophilized powder with sterile water. It's approved only for HIV-associated lipodystrophy with excess visceral fat, based on phase 3 trials [1]. Any other use is off-label.
What is the actual FDA-approved way to take tesamorelin?
Tesamorelin is given as a once-daily subcutaneous injection, self-administered by the patient, into the abdomen (avoiding the navel and any scar tissue). The approved formulation, sold as Egrifta and its follow-on Egrifta SV, is a lyophilized powder that has to be reconstituted with sterile water immediately before each injection. It is not an oral drug, not a nasal spray, and not something you take with food. It is injected at night, on an empty stomach, because growth hormone release pulses naturally overnight and food intake blunts the GHRH response. The approval is narrow. The FDA cleared tesamorelin for reduction of excess visceral adipose tissue in HIV-infected patients with lipodystrophy, based on two pooled phase 3, multicenter, double-blind, placebo-controlled trials with safety extension data [1]. That is the only indication with real regulatory trial evidence behind it. People using it for general fat loss, bodybuilding, or anti-aging reasons are doing something off-label, meaning there's no FDA-reviewed trial in that population confirming the same benefit-risk balance. A 2011 Nature Reviews Drug Discovery profile summarizes tesamorelin as a growth hormone releasing hormone (GHRH) analogue developed specifically to address this fat redistribution problem in HIV patients [2]. That's the drug's actual origin story, not a general metabolic enhancer.
What dose of tesamorelin do you actually inject?
The approved dose is 2mg once daily by subcutaneous injection, reconstituted from the lyophilized vial. Egrifta SV, the newer formulation, delivers this as a 2mg dose in a smaller reconstitution volume than the original Egrifta, which improved comfort and reduced injection site reactions somewhat, though both work through the same mechanism. The main phase 3 program that got tesamorelin approved tested this dose against placebo over 26-week treatment periods with safety extensions, and it's the dose basis for essentially every efficacy number quoted for this drug [1]. A population pharmacokinetics analysis pooling data from HIV-infected patients and healthy subjects confirmed that tesamorelin's clearance and exposure are reasonably predictable across body weights at this fixed dose, without a strong signal that heavier patients need dose adjustment [3]. For exact instructions on drawing up the powder, mixing ratios, and what the reconstituted solution should look like, see our dedicated guide on tesamorelin reconstitution. Don't guess at concentrations. Getting the reconstitution volume wrong changes your actual dose even if you draw up the same number on the syringe.
When and where should you inject tesamorelin?
Inject at bedtime, subcutaneously, into the abdomen. That's the routine used in the trials and the one on the approved label. Rotate the exact injection site within the abdomen each night (move at least an inch from the last spot) to reduce the chance of localized reactions or lumps building up in one area. Timing matters more with tesamorelin than with a lot of other injectables because it works by stimulating your own pituitary to release growth hormone in a pulse, mimicking the body's natural nighttime GH surge. Injecting on an empty stomach, and at night, lines the drug up with that natural rhythm rather than fighting it. Don't inject into the same exact spot repeatedly. Don't inject through clothing. Don't reuse a needle. These aren't tesamorelin-specific rules, they're basic subcutaneous injection hygiene, but they matter because injection site reactions (erythema, pruritus, sometimes nodules) are among the most commonly reported side effects in the trials [4] [5].
How long does it take to reconstitute and inject tesamorelin?
Reconstitution takes a few minutes: withdraw the sterile water diluent, inject it into the powder vial, gently swirl (don't shake) until fully dissolved, let any foam settle, then draw up your dose. The injection itself takes seconds once the syringe is loaded. The solution should look clear and colorless to slightly yellow. If it looks cloudy, has visible particles, or the vial was dropped or damaged, don't use it. Reconstituted tesamorelin is not meant to sit around for days; use it promptly and follow storage guidance for the interval between mixing and injecting. This is not a supplement you toss in a drawer and forget about. Store unreconstituted vials refrigerated, protect from light, and treat the whole process the way you'd treat any injectable prescription medication: careful hands, clean surface, one vial at a time.
How long before tesamorelin actually shows results?
In the pooled phase 3 trials, visceral adipose tissue reductions were measured at 26 weeks (roughly 6 months), which is the timeframe the approval and most efficacy claims are based on [1]. This is not a drug that shows a visible difference in two weeks. A meta-analysis of randomized controlled trials on tesamorelin's body composition, hepatic fat, and metabolic outcomes in HIV-associated lipodystrophy reinforces that measurable visceral fat and liver fat changes track with these multi-month trial windows, not with days or a couple of weeks [6]. Separately, a study specifically on fat quality found that tesamorelin can improve fat quality markers somewhat independently of the amount of fat lost, meaning some of what's happening physiologically doesn't show up as a smaller waistline number right away [7]. If someone is expecting a dramatic visible change inside a month, that expectation isn't supported by the trial timelines this drug was actually studied on.
What happens if you stop taking tesamorelin?
The phase 3 program included safety extension data, and one consistent theme across the tesamorelin literature is that benefits are not necessarily permanent once you stop. Visceral fat and metabolic parameters were tracked across extended treatment periods, but tesamorelin's effect works through ongoing GHRH stimulation, meaning it needs continued dosing to keep driving the same growth hormone pulse pattern that reduces visceral fat. Think of it less like a one-time reset and more like a medication that needs to stay active in your system to keep doing its job, similar to how blood pressure medication doesn't fix blood pressure permanently after you stop it. There is no phase 3 trial data supporting indefinite benefit retention after discontinuation, and prescribers should set that expectation clearly before someone starts.
How does tesamorelin dosing compare across the trial evidence?
| Parameter | Approved / trial-tested value | Source | |
|---|---|---|---|
| Route | Subcutaneous injection | Pooled phase 3 trials [1] | |
| Dose | 2mg once daily | Pooled phase 3 trials [1] | |
| Timing | Nightly, empty stomach | Clinical pharmacokinetics analysis [3] | |
| Trial duration measured | 26 weeks (with safety extensions) | Pooled phase 3 trials [1] | |
| Approved population | HIV-associated lipodystrophy, excess visceral fat | Pooled phase 3 trials [1] | |
| Liver fat outcome studied | Randomized, double-blind NAFLD trial in HIV | Lancet HIV, 2019 [8] | For a full breakdown of dosing schedules, titration questions, and what a typical prescribing plan looks like, see tesamorelin dosage. If you want to check your own reconstitution math against a standard 2mg protocol, the tesamorelin dosage calculator walks through the volumes. |
What does tesamorelin actually do to visceral fat and the liver?
The core approved effect is visceral adipose tissue reduction, confirmed in the pooled phase 3 placebo-controlled trials [1]. Beyond fat volume, a randomized double-blind multicenter trial specifically tested tesamorelin's effect on non-alcoholic fatty liver disease in HIV patients and found benefit on liver fat content, published in The Lancet HIV [8]. A related study found visceral fat reduction with tesamorelin correlated with improved liver enzyme levels [9]. Mechanistic work has gone further than just the fat scan numbers. A JCI Insight study looked at hepatic transcriptomic signatures after tesamorelin treatment in HIV-associated NAFLD and found gene expression changes consistent with the metabolic benefit [10], and a Scientific Reports paper used targeted proteomics and transcriptomics to try to map out the actual response pathways involved [11]. There's also data on inflammatory markers: one study found reductions in visceral fat correlated with changes in inflammatory markers in this same patient population [12]. None of this is evidence for using tesamorelin as a general weight-loss drug in someone without HIV-associated lipodystrophy. The entire evidence base sits inside that specific population.
Do you need a prescription, and where does it legally come from?
Yes. Tesamorelin as the FDA-approved drug (Egrifta/Egrifta SV) requires a prescription and is dispensed through a pharmacy. Compounded versions of tesamorelin also exist, and the regulatory picture there is different: bulk tesamorelin has been nominated for the FDA's 503A bulk drug substances list for compounding [13], and separately there's a 503B outsourcing facility bulks list [14] under the compounding provisions of federal drug law [15]. Being nominated for a list is not the same as full FDA approval of a finished drug product; compounded tesamorelin is not reviewed by the FDA the same way Egrifta was. This matters for how you take it, too. An approved product comes with an FDA-reviewed label specifying dose, reconstitution instructions, and storage. A compounded product's instructions come from the compounding pharmacy, and quality can vary. If you're evaluating where to source it and what it should reasonably cost, tesamorelin cost breaks down the price difference between branded and compounded routes. The provider-reviewed route through Tesamorelin Co connects patients with a fulfilling pharmacy partner rather than compounding anything in-house.
What are the common side effects while you're on it?
Injection site reactions (redness, itching, occasional bruising or lumps) are among the most frequently reported issues in the trial data [4] [5]. Joint pain, muscle aches, and swelling (edema) related to fluid retention from growth hormone stimulation also show up, which is consistent with how GH-axis drugs generally behave [16]. A newer post hoc analysis looked specifically at whether patients with or without dorsocervical fat (the so-called "buffalo hump" fat pad sometimes seen in HIV lipodystrophy) had different tesamorelin responses in the phase 3 trial data, and it's a useful read for anyone with that specific fat distribution pattern [17]. Separately, a 2024 study in AIDS journal looked at efficacy and safety specifically in people on modern integrase inhibitor HIV regimens, which matters because HIV treatment itself has changed a lot since the original phase 3 trials were run [18]. For the full list of documented adverse effects, how common each one is, and what warrants stopping treatment, see tesamorelin peptide side effects.
Does tesamorelin help with anything besides visceral fat?
There's emerging research outside the core fat indication, but it's not the same tier of evidence as the phase 3 lipodystrophy trials. A 2025 study in The Journal of Infectious Diseases looked at tesamorelin's effects on neurocognitive impairment in people with HIV and abdominal obesity [19]. That's a real, published trial, but it's investigating a different outcome (cognition) in a specific comorbid population, not a general claim about brain benefits for anyone taking the drug. Broader peptide therapy reviews, including a 2026 orthopaedic peptide review [20] and a sports medicine primer on injectable peptide therapy [21], mention GHRH analogues like tesamorelin in passing as part of the wider peptide landscape, but neither is a tesamorelin-specific efficacy trial for musculoskeletal or performance use. A 2026 Sports Medicine review on approved and unapproved peptide therapies for musculoskeletal injuries and athletic performance likewise covers the category broadly rather than establishing tesamorelin-specific performance claims [22]. Bottom line: if someone tells you tesamorelin is proven for cognition, joints, or athletic performance, ask them to name the trial. The approved indication, and the strongest trial evidence, is visceral fat reduction in HIV-associated lipodystrophy [1].
How do you know if tesamorelin is even the right drug for your situation?
Tesamorelin's approval and trial base is specifically for HIV-associated lipodystrophy, a distinct medical condition involving abnormal fat redistribution, not ordinary abdominal fat from diet or aging. A clinical review on approaching the patient with lipodystrophy outlines how this condition is actually diagnosed, which involves clinical exam and often imaging, more than a visual assessment of belly fat [23]. A separate paper on diagnosing lipodystrophy syndromes goes into the same distinction in more depth [24]. If you don't have HIV-associated lipodystrophy, you may still be offered tesamorelin off-label, and that's a decision to make with a prescriber who is honest with you about the evidence gap. The trial data doesn't disappear just because the population using it has changed, but it also doesn't automatically transfer. Ask specifically what evidence applies to your situation versus what applies to the approved population. Start with the full picture of what the drug is and isn't at tesamorelin before deciding on a dosing plan.
Frequently asked questions
How often do you inject tesamorelin?
Once daily, every night, by subcutaneous injection into the abdomen. This matches the dosing schedule used in the pooled phase 3 trials that led to FDA approval for HIV-associated lipodystrophy, and it's the schedule reflected on the approved drug label [2]. Skipping doses or dosing less frequently wasn't the tested protocol and isn't expected to reproduce the same visceral fat reduction results.
Can you take tesamorelin orally instead of injecting it?
No. Tesamorelin is a peptide, and peptides are broken down by digestive enzymes if swallowed, which is why the approved formulation is a subcutaneous injection only. There is no FDA-approved oral tesamorelin product. Anything sold as an oral tesamorelin product is outside the approved drug's formulation and evidence base entirely.
Do you need to inject tesamorelin on an empty stomach?
Yes, the approved dosing instructions call for injection at night on an empty stomach. This timing lines up with the body's natural overnight growth hormone pulse, which is the physiological process tesamorelin is designed to stimulate through GHRH receptor activation. Eating around injection time is not part of the tested protocol from the phase 3 trials [2].
How long does a vial of tesamorelin last after reconstitution?
Reconstituted tesamorelin should be used promptly rather than stored for extended periods; check the specific product labeling or your pharmacy's instructions for exact storage windows, since original Egrifta and Egrifta SV formulations have somewhat different handling instructions. Discard any solution that looks cloudy or has particles, and never reuse diluent or needles across vials.
Is tesamorelin approved for weight loss in people without HIV?
No. The FDA approval covers reduction of excess visceral adipose tissue specifically in HIV-infected patients with lipodystrophy, based on the pooled phase 3 trial data [2]. Use in people without HIV-associated lipodystrophy, including for general weight loss or body composition goals, is off-label, meaning there's no FDA-reviewed trial confirming the same benefit-risk profile in that population.
What is the difference between Egrifta and Egrifta SV?
Egrifta SV is a newer formulation of the same tesamorelin drug, reconstituted in a smaller volume than the original Egrifta, which many patients find more comfortable to inject. Both deliver the same 2mg once-daily dose and work through the same GHRH mechanism; the difference is formulation and injection volume, not the active drug or the approved indication.
Does tesamorelin need to be refrigerated?
Unreconstituted tesamorelin vials generally require refrigeration and protection from light; check your specific product's storage instructions, since handling can differ slightly between Egrifta, Egrifta SV, and compounded versions. Reconstituted solution has its own separate, shorter storage window. Don't assume compounded product storage rules match the branded product exactly.
How long until you see visceral fat reduction from tesamorelin?
The phase 3 trials measured visceral adipose tissue reduction at 26 weeks (about 6 months) of treatment [2]. A related meta-analysis of randomized controlled trials confirms body composition and hepatic fat changes track with multi-month treatment, not days or a couple of weeks [7]. Expect a gradual change measured in months, not a quick before-and-after.
What happens to visceral fat if you stop tesamorelin?
Tesamorelin works by stimulating ongoing growth hormone release through GHRH receptor activation; it doesn't permanently reset fat storage. There's no phase 3 trial evidence showing visceral fat reduction is maintained indefinitely after stopping the drug, so benefits are generally expected to depend on continued treatment, similar to many other maintenance medications.
Can tesamorelin help with fatty liver disease?
A randomized, double-blind, multicenter trial published in The Lancet HIV tested tesamorelin specifically for non-alcoholic fatty liver disease in HIV patients and found a benefit on liver fat content [9]. Related research found visceral fat reduction on tesamorelin correlated with improved liver enzyme levels [10]. This evidence is specific to the HIV-associated lipodystrophy population studied.
Where on the body do you inject tesamorelin?
Into the subcutaneous fat of the abdomen, avoiding the navel area and any scar tissue, rotating the exact spot each night. This is the injection site used throughout the phase 3 program and reflected in approved dosing instructions [2]. Consistent site rotation reduces the risk of localized skin reactions building up in one spot.
Do you need a prescription to get tesamorelin?
Yes, the FDA-approved product (Egrifta/Egrifta SV) is prescription-only and dispensed through a pharmacy. Compounded tesamorelin also exists under separate compounding regulations governing bulk drug substances [14][16], but it still requires a prescriber's order; it is not available over the counter under any legitimate pathway.
Sources
- PubMed, Nature Reviews Drug Discovery: Tesamorelin is profiled as a GHRH analogue developed for HIV-associated lipodystrophy
- PubMed, J Clin Endocrinol Metab 2010: Pooled analysis of two multicenter, double-blind, placebo-controlled phase 3 trials with safety extension data established the 2mg once-daily subcutaneous dosing and 26-week efficacy timeframe for HIV-associated excess abdominal fat
- PubMed, Clinical Pharmacokinetics 2015: Population pharmacokinetic analysis of tesamorelin across HIV-infected patients and healthy subjects
- PubMed, Drugs 2011 review: Review of tesamorelin's use and safety profile in HIV-associated lipodystrophy including injection site reactions
- PubMed, Annals of Pharmacotherapy 2012: Tesamorelin reviewed as a GHRH analogue for HIV-associated lipodystrophy with associated adverse effect profile
- PubMed, Obesity Research & Clinical Practice 2026: Meta-analysis of RCTs on tesamorelin body composition, hepatic fat, metabolic and safety outcomes in HIV-associated lipodystrophy
- PubMed, AIDS 2021: Tesamorelin improves fat quality independent of changes in fat quantity
- PubMed, Lancet HIV 2019: Randomized, double-blind, multicenter trial of tesamorelin for non-alcoholic fatty liver disease in HIV
- PubMed, AIDS 2017: Visceral fat reduction with tesamorelin is associated with improved liver enzymes in HIV
- PubMed, JCI Insight 2020: Tesamorelin affects hepatic transcriptomic signatures in HIV-associated NAFLD
- PubMed, Scientific Reports 2021: Targeted proteomic and transcriptomic approach delineating tesamorelin response pathways in HIV-associated NAFLD
- PubMed, AIDS 2011: Tesamorelin's effects on inflammatory markers relate to visceral adipose reduction
- FDA, Bulk drug substances nominated for use in compounding under section 503A: Tesamorelin's status on the FDA bulk drug substances nomination list relevant to 503A compounding
- eCFR, 21 CFR 216.24, the 503B Bulks List: Separate regulatory list governs bulk drug substances for 503B outsourcing facility compounding
- Cornell Law, 21 U.S.C. 353a, pharmacy compounding: Federal statute governing pharmacy compounding conditions under section 503A
- PubMed, Best Practice & Research Clinical Endocrinology & Metabolism 2013: Growth hormone axis stimulation is associated with fluid retention and joint/muscle related effects
- PubMed, Journal of Clinical and Translational Science 2023: Post hoc analysis of phase 3 trial comparing tesamorelin effect in people with and without dorsocervical fat
- PubMed, AIDS 2024: Efficacy and safety of tesamorelin evaluated in people with HIV on integrase inhibitor regimens
- PubMed, Journal of Infectious Diseases 2025: Study of tesamorelin's effects on neurocognitive impairment in persons with HIV and abdominal obesity
- PubMed, JAAOS Global Research & Reviews 2026: Review of therapeutic peptides in orthopaedics covering applications and challenges
- PubMed, American Journal of Sports Medicine 2026: Primer on injectable peptide therapy for orthopaedic and sports medicine physicians
- PubMed, Sports Medicine 2026: Review of safety and efficacy of approved and unapproved peptide therapies for musculoskeletal injuries and athletic performance
- PubMed, Journal of Clinical Endocrinology and Metabolism 2022: Clinical approach to diagnosing and managing the patient with lipodystrophy
- PubMed, Annales d'Endocrinologie 2012: Diagnostic approach to lipodystrophy syndromes