Reference

Last reviewed: 29 Apr 2026
Sources cited: 10

Compound class~5,196 Da

Synthetic GHRH analogue — full-length GHRH(1-44) with N-terminal hexenoyl modification

44-residue peptide matching the native human GHRH(1-44) sequence with a 6-carbon trans-3-hexenoyl group attached to the N-terminal tyrosine. The hexenoyl modification resists DPP-IV cleavage at the Tyr¹–Ala² bond. The standard 3-letter sequence parser cannot handle the N-terminal acyl modification, hence the fallback.

Tesamorelin

Last verified: 2026-04-29

At a glance


Also known as	Egrifta, Egrifta SV, Egrifta WR (F8 formulation), TH9507, tesamorelin acetate
Class	Synthetic GHRH analogue — full-length human GHRH(1-44) with N-terminal hexenoyl modification for DPP-IV resistance
Typical route	Subcutaneous injection, daily
Half-life	~26 minutes (IV); the N-terminal hexenoyl group extends effective duration relative to native GHRH(1-44)1
Molecular weight	~5,196 Da (the largest peptide in the GH cluster)
Sequence	hexenoyl-Tyr-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Met-Ser-Arg-Gln-Gln-Gly-Glu-Ser-Asn-Gln-Glu-Arg-Gly-Ala-Arg-Ala-Arg-Leu-NH₂ (44 amino acids — the native human GHRH(1-44) full sequence with an N-terminal hexenoyl moiety on Tyr¹)
UK status	Not approved as a licensed UK medicine. No NHS or private-prescription pathway. Sold as a research chemical.
US status	FDA-approved as Egrifta (2010); Egrifta SV (F4 formulation) and Egrifta WR (F8 formulation) currently licensed for HIV-associated lipodystrophy.1 5 Off-label use for general visceral fat or anti-ageing is common in the biohacker space but not within-label.

What it is

Tesamorelin is the only currently FDA-approved compound in the GH-axis cluster of this encyclopedia. It is the full-length 44-amino-acid human GHRH sequence with a single chemical modification — a hexenoyl group on the N-terminal tyrosine — that protects it from rapid cleavage by dipeptidyl peptidase-IV (DPP-IV), the same enzyme CJC-1295 was engineered to resist.

It was approved in 2010 (Egrifta) and again in updated formulations (Egrifta SV in 2019, Egrifta WR / F8 in the mid-2020s) for a single, narrow indication: reduction of excess visceral abdominal fat in HIV-infected patients with lipodystrophy. This is a real medical population — patients on antiretroviral therapy whose treatment can drive a specific pattern of abdominal fat accumulation that is metabolically and cosmetically distressing.

The biohacker space uses tesamorelin off-label for the same biology — visceral fat reduction — in HIV-negative populations. The pharmacology that drives the on-label effect (GHRH-receptor pulsatile agonism → GH elevation → IGF-1 elevation → preferential visceral fat loss) is not HIV-specific. Whether the magnitude of effect translates to non-HIV populations is the open question, and the two pieces of evidence available are: (a) the lipodystrophy trial population had Phase 3 outcome data showing 15.2% VAT reduction at 26 weeks; (b) a smaller controlled trial in obese non-HIV adults showed similar VAT reduction plus measurable improvement in cardiovascular risk markers (cIMT, CRP, triglycerides).

It is not human growth hormone. Like the rest of the cluster, tesamorelin asks the pituitary to release more of its own GH; it doesn’t replace GH itself.

Mechanism

Tesamorelin is a full agonist at the growth hormone-releasing hormone receptor (GHRH-R) on pituitary somatotrophs — the same receptor sermorelin and CJC-1295 target.5

Two design choices distinguish tesamorelin from the other GHRH analogues in this encyclopedia:

Full-length GHRH(1-44) sequence rather than the 1-29 fragment. Sermorelin and CJC-1295 use the shortest fully-active GHRH fragment (1-29). Tesamorelin uses the entire native 44-residue sequence, including residues 30-44 that aren’t strictly required for receptor activation but contribute to physiological binding behaviour and feedback signalling.
N-terminal hexenoyl modification. A 6-carbon trans-3-hexenoyl group attached to the N-terminal tyrosine resists DPP-IV cleavage at the Tyr¹–Ala² bond — the same enzymatic vulnerability CJC-1295 addresses by substituting D-Ala at position 2. The strategy is different (chemical addition vs amino-acid substitution); the result is similar.

Together, these choices give tesamorelin a half-life modestly longer than native GHRH but shorter than CJC-1295 no-DAC, and a pulse pattern that the body’s somatostatin counter-regulation responds to normally — preserving negative feedback in a way the stability substitutions in CJC-1295 theoretically (but not directly demonstrably) compromise.

The downstream cascade is the same as the rest of the GHRH-class: GHRH-R activation → cAMP elevation in somatotrophs → GH exocytosis → hepatic IGF-1 production. The clinical trials documented an 81% increase in IGF-1 at the approved 2 mg daily dose over 26 weeks, with the visceral fat reduction (15.2% mean) tracking that IGF-1 elevation.6

The mechanism gives a pulse of GH similar to sermorelin or CJC-1295 no-DAC, but the published outcome data — VAT reduction, IGF-1 elevation, lipid improvement, CV-marker improvement — is far stronger for tesamorelin than for any other compound in the GH cluster. This is the fact that justifies tesamorelin’s higher cost and dose-precision requirements.

Routes of administration

Subcutaneous injection (the only studied route)


Bioavailability	Sufficient for the documented VAT and IGF-1 effects
Onset	GH pulse peaks within ~1 hour post-injection
Duration	2–4 hours per dose; full clearance under 6 hours
Approved dose	2 mg subQ once daily (continuous, no cycling) per the FDA label
Off-label community dose	1 mg subQ daily, 5 on / 2 off, cycled 8 weeks on / 8 weeks off
Equipment (Egrifta SV)	Pharmaceutical kit with prefilled diluent vial, supplied syringes, alcohol swabs
Equipment (research-chem)	Insulin syringe (29G–31G, U-100), bacteriostatic water, alcohol wipes
When this route makes sense	Default and only viable route. All clinical data is subQ.

The clinical trials standardised on subQ daily dosing in the abdomen, consistent with the indication (subcutaneous reduction of visceral abdominal fat). Site rotation across the abdomen is standard practice.

Intravenous (research / pharmacokinetic only)

IV dosing was used to characterise PK in development (the ~26-minute half-life figure derives from IV studies) but is not a clinical or community route.

Intramuscular, oral, sublingual, intranasal

Not viable. Tesamorelin is GI-degraded; its size (44 residues, ~5.2 kDa) prevents reliable absorption through any non-injection route. IM is mechanically possible but offers no advantage over subQ.

Cross-route comparison

SubQ daily is the only meaningful route. All clinical evidence, all dosing protocols, and all community use centre on subQ. The route question for tesamorelin is dose timing (typically morning) and which formulation (pharmaceutical Egrifta SV vs research-chem vial), not which administration route.

What the evidence says

Honest summary: tesamorelin has the strongest outcome-trial evidence base of any compound in the GH cluster of this encyclopedia. The data is in HIV-associated lipodystrophy, which is the FDA-approved indication. Off-label use in HIV-negative populations is mechanistically supported by a smaller obesity trial but is not within-label.

Phase 3 trials in HIV lipodystrophy (the registrational evidence)

Two pivotal randomised, double-blind, placebo-controlled Phase 3 trials enrolled 404 HIV-infected adults with lipodystrophy and excess abdominal fat to receive 2 mg daily tesamorelin or placebo for 26 weeks.6

Outcomes at 26 weeks:

Endpoint	Tesamorelin 2 mg	Placebo
Visceral adipose tissue (VAT)	−15.2%	+5.0%
IGF-1	+81.0%	−5.0%
Triglycerides	−50 mg/dL	+9 mg/dL
Total cholesterol / HDL ratio	−0.31	+0.21

The VAT reduction was measured by CT scan, the gold standard for visceral fat assessment. The IGF-1 elevation tracks the proposed mechanism. The lipid improvements were a secondary endpoint that the trial wasn’t powered to assess on its own but were consistent and reproducible across the population.

Adverse events were dominated by injection-site reactions and arthralgia (joint pain), with rates roughly twice placebo. The safety profile was acceptable enough for FDA approval at this duration.

Phase 2 trial in non-HIV obese adults (the strongest off-label evidence)

A smaller controlled trial in obese non-HIV adults with reduced GH secretion examined tesamorelin at the same 2 mg daily dose. VAT improvements, carotid intima-media thickness (cIMT), log C-reactive protein, and triglycerides all improved significantly in the tesamorelin group versus placebo.7

This is the strongest evidence available for the biohacker use case. Two caveats: (a) the trial selected for “reduced GH secretion” — not all obese adults have this baseline; (b) it’s smaller-N and shorter-duration than the HIV registrational trials.

Long-term cardiovascular safety: not established

Tesamorelin’s full prescribing information explicitly states “long-term cardiovascular safety of tesamorelin has not been established.”3 The pivotal trials ran 26 weeks; the open-label extension data extends modestly beyond that. Multi-year cardiovascular outcomes — the kind that semaglutide has via SELECT — do not exist for tesamorelin.

What the evidence does NOT show

No outcome trials in HIV-negative populations beyond the obesity Phase 2. Anti-ageing, recovery, body-composition use in healthy biohackers is mechanistic extrapolation from the lipodystrophy and obesity data.
No comparative data between formulations. Egrifta (original), Egrifta SV (F4), and Egrifta WR (F8) differ in stability and reconstitution but the registrational trials used the original formulation.
No data on stacking with ipamorelin or other GHRPs at any controlled level. The “reduce tesamorelin by 30% when stacked with ipamorelin” community rule is dose-response inference, not measured.
No long-term receptor desensitisation characterisation beyond the trial duration.

Typical use patterns

On-label use (HIV-associated lipodystrophy)

The FDA label specifies 2 mg subQ daily, continuous (no cycling). Patients are typically prescribed Egrifta SV or Egrifta WR through HIV specialty pharmacies under HIV-care provider supervision. Treatment duration is open-ended; some patients run continuously for years on the licensed protocol.

Off-label community use (visceral fat / metabolic optimisation)

The biohacker community has standardised on a different protocol than the FDA label, primarily for cost and tolerance reasons:

1 mg subQ daily (half the licensed dose) — the most common community dose
5 days on, 2 days off weekly cycling
8 weeks on, 8 weeks off longer-cycle
Morning injection rather than bedtime (tesamorelin is more about IGF-1 elevation than nighttime GH-pulse alignment, and the licensed trials used morning dosing)

This protocol uses roughly 30% of the cumulative compound the licensed protocol uses (1 mg × 5/7 days × 50% duty cycle) and is the basis for the cost figures community vendors quote. It is not within-label and has not been studied for efficacy at this dose schedule. The mechanistic case is reasonable: at half-dose with cycling, a user is still producing meaningful GH pulses and IGF-1 elevation, just with smaller per-cycle exposure.

Stacking with ipamorelin

The community-standard dose-modifier rule: reduce tesamorelin by ~30% when stacking with ipamorelin. The reasoning is that ipamorelin’s GHSR-1a pulse adds to tesamorelin’s GHRH-R pulse synergistically, so the same total GH output is achieved with less tesamorelin. The rule is heuristic, not measured.

Typical stacked protocol:

Tesamorelin: 0.7 mg daily (down from 1 mg) + Ipamorelin: 200–300 mcg daily
5 days on, 2 days off
Morning injection (different from CJC-1295 + ipamorelin’s bedtime convention — tesamorelin’s IGF-1-driven mechanism doesn’t require sleep alignment the way GHRP-pulse-driven sleep architecture does)

Why a user would choose tesamorelin over sermorelin or CJC-1295

The outcome data. No other compound in the GH cluster has 15.2% VAT reduction documented in a Phase 3 trial.
Visceral-fat targeting specifically. The licensed indication is exactly this; the trials measured exactly this.
Currently FDA-approved. Sermorelin’s approval was withdrawn in 2009; CJC-1295 and ipamorelin were never approved.

Why a user would choose CJC-1295 or sermorelin over tesamorelin

Cost. Tesamorelin is the most expensive compound in the GH cluster. Pharmaceutical Egrifta SV runs ~$3,000/month; research-chem tesamorelin is more accessible but still typically more per-mg than CJC-1295 or sermorelin.
Dose burden. 1–2 mg daily injections vs the 100–300 mcg daily / weekly DAC alternatives.
Reconstituted vial shelf life. Research-chem tesamorelin in BAC water is stable for ~7 days, much shorter than the 28-day standard for the rest of the GH cluster.
Fit-for-purpose. Users primarily interested in sleep architecture or GH-pulse mimicry, rather than visceral-fat-specific outcomes, get most of the relevant biology from less expensive compounds.

Stacking beyond ipamorelin

BPC-157 / TB-500: common during recovery phases. No documented interactions.
NAD+ precursors, MOTS-c: common in longevity stacks. No documented interactions.
Other GHRH analogues (sermorelin, CJC-1295): redundant — same receptor.
HGH: redundant.
GLP-1 agonists (semaglutide, tirzepatide): common pairing in the metabolic-optimisation crowd. No documented direct interaction; both compounds independently improve metabolic markers. Be aware that GH transiently antagonises insulin and GLP-1 enhances insulin secretion — the net effect on glucose control varies and is worth monitoring.

For sensitive systems

Tesamorelin’s profile in sensitive-systems users diverges from the rest of the GH cluster in two important ways: the per-injection dose is 5–10× larger (1–2 mg vs 100–300 mcg), and the per-dose IGF-1 elevation is much larger (the registrational trials documented 81% IGF-1 increase vs the modest elevations the GHRP-stack protocols produce).

Both differences argue for more cautious starting and ramping than for ipamorelin, sermorelin, or CJC-1295.

Start dose for sensitive users. 0.5 mg subQ in the morning, 5 days on / 2 days off. Hold for 2–3 weeks before considering an increase. The community-standard 1 mg dose is a reasonable target but not a starting point for users with reactive nervous or immune systems.

Ramp. If tolerated, increase to 0.75 mg, then 1 mg over 4–6 weeks. The 2 mg licensed dose is rarely the right target for off-label users, especially sensitive-systems users — the side-effect curve climbs faster than the benefit curve in this dose range.

Expected adjustment profile:

Injection-site reactions — pain, redness, mild swelling. The most consistently reported AE in the registrational trials, occurring at roughly twice the placebo rate.
Joint pain (arthralgia) — the second-most-common AE in the trials. IGF-1-driven; dose-dependent and reversible.
Mild headache in the first few days — vasoactive, GH/IGF-1-driven fluid shifts.
Tingling, numbness, or carpal-tunnel-like sensations — fluid retention pressing on peripheral nerves. Worth flagging because the larger IGF-1 elevation makes this more likely than with ipamorelin or low-dose CJC-1295. More common at the 2 mg dose than at 1 mg.
Mild peripheral oedema — ankle swelling, ring tightness, morning facial puffiness. Same fluid-retention mechanism. Reversible with dose reduction.
Vivid dreaming in the first 1–2 weeks.

What’s not normal and warrants stopping: persistent paraesthesia not reversing on dose reduction, sustained joint pain that wasn’t there at baseline, blood-pressure elevation, oedema that progresses rather than stabilises, atypical chest sensations, new glucose dysregulation in users tracking it. The IGF-1 elevation is real and measurable; if signals cluster, get an IGF-1 blood test.

For MCAS / histamine-sensitive users. No specific histamine activity documented. Injection-site reactions are local and not generally indicative of systemic mast-cell activation, but the larger per-injection volume (relative to GHRP doses) makes local reactivity more visible.

For POTS users. The fluid-retention footprint is the largest of any compound in the GH cluster. Monitor for orthostatic worsening especially in the first 4 weeks. Sensitive-start dosing (0.5 mg) and slow ramping are the cautious approach. Some POTS users find tesamorelin tolerable; others find the fluid retention enough to outweigh the metabolic benefit.

For UARS / chronic fatigue / ME/CFS. Tesamorelin is less directly aligned with the sleep-architecture use case than ipamorelin or sermorelin (different mechanism focus, different timing). Worth a 4-week trial only if visceral fat or IGF-1 elevation is the actual target; otherwise the GH cluster has cheaper, lower-dose-burden options.

For active or recent cancer history. Same relative contraindication as the rest of the GH cluster, with one specific caution: tesamorelin’s 81% IGF-1 elevation is the largest documented in the cluster. The mechanistic concern about GH/IGF-1-driven mitogenicity is most acute for this compound. Treat as a relative contraindication for active malignancy, recent (within ~5 years) malignancy of GH/IGF-1-responsive types (breast, prostate, colon, certain endocrine tumours), MEN syndromes, or strong family history of GH/IGF-1-responsive cancers without screening in place.

For diabetes (especially type 2). GH transiently antagonises insulin. The HIV-lipodystrophy trial population had elevated diabetes rates and tesamorelin produced modest increases in fasting glucose and HbA1c — not enough to derail the approval but documented and consistent. The label includes a caution about glucose monitoring in diabetic and prediabetic patients.

Interactions worth considering:

HGH: redundant.
Other GHRH analogues: redundant.
Insulin / metformin / GLP-1 agonists: monitor glucose; GH transiently antagonises insulin.
Steroids: corticosteroids blunt GHRH pulse response.
SSRIs, SNRIs, LDN, beta-blockers: no documented interactions.

Reasonable expectations

Onset. Subjective effects, where present, build slowly — the visceral-fat reduction and IGF-1 effects need 6–12 weeks of consistent dosing to be measurable. Unlike ipamorelin or sermorelin, tesamorelin doesn’t typically produce a rapid sleep-quality change in the first 1–2 weeks; the mechanism is IGF-1-driven and slower.

Response rate. In the registrational HIV-lipodystrophy trials, VAT reduction ≥8% (a clinically meaningful threshold) was achieved by a substantial majority of treated patients — the population was selected for excess VAT, which biases the response rate up. In off-label HIV-negative populations, response rates are not directly characterised; the obesity Phase 2 trial showed similar VAT reduction patterns at the trial-population level.

What the evidence actually supports.

Visceral adipose tissue reduction (~15% in the trial population) — strongly supported by Phase 3 outcome data.
IGF-1 elevation — strongly supported (81% increase at 2 mg/day for 26 weeks).
Triglyceride reduction — supported as a secondary endpoint.
Cardiovascular risk-marker improvement (cIMT, CRP) — supported in the obesity trial; not yet shown for hard CV outcomes.
Improved fat quality independent of fat quantity — a 2021 substudy showed fat-tissue quality measures (ectopic lipid, adipocyte size) improved beyond what VAT mass reduction alone would predict.8

What the evidence does not support.

General “anti-ageing” claims — tesamorelin is studied for visceral fat, not lifespan or healthspan endpoints.
Body-composition outcomes outside the visceral-fat picture — lean mass changes were modest in the trials, not the primary effect.
Hard cardiovascular outcomes (MI, stroke, mortality) — improving CV markers is not the same as improving CV outcomes; that data doesn’t exist for tesamorelin.

What not to expect.

HGH-equivalent body composition effects. Tesamorelin elevates IGF-1 and reduces visceral fat; it does not produce HGH’s broad lean-mass-promoting effects at therapeutic doses.
Rapid sleep architecture changes. This is not the compound’s strongest use case in the GH cluster.
Effect at sub-1 mg doses comparable to the 2 mg trial outcomes. The community 1 mg protocol is a cost-tolerance compromise; 50% of the studied dose may produce less than 50% of the studied effect.

Cost

Tesamorelin is the most cost-volatile compound in the GH cluster, with a 50–100× spread between pharmaceutical and research-chemical access paths.

US pharmaceutical (Egrifta SV / Egrifta WR)

Component	Typical monthly cost
Egrifta SV / WR (medication only)	~$3,000+/month at the licensed 2 mg daily dose
Specialty pharmacy and HIV-care provider supervision	Insurance-dependent; typically covered for HIV lipodystrophy patients
Out-of-pocket (off-label without insurance coverage)	Frequently prohibitive without manufacturer assistance programs

Egrifta SV/WR is dispensed through HIV specialty pharmacies on prescription. Off-label use is possible but requires a prescriber willing to write outside the licensed indication and a patient willing to pay out-of-pocket. Manufacturer patient assistance programs exist for the licensed indication but generally don’t cover off-label use.

US compounded (limited)

Tesamorelin is not as widely accessible through 503A compounding pharmacies as sermorelin. Some compounding pharmacies dispense tesamorelin under specific protocols, but it’s a less common compounded peptide than sermorelin or ipamorelin. Where available, monthly costs run approximately $200–500/month at the community 1 mg/day protocol.

Research-chemical (UK and US)

Research-chem tesamorelin is the dominant access path for the biohacker community:

5 mg vials: ~£25–80 / $30–100
10 mg vials: ~£40–120 / $50–150
Monthly cost at 1 mg/day, 5 days/week: roughly £30–90 / $40–120/month

Sensitive-start economics

A 0.5 mg/day starting dose halves the consumption again — a 5 mg vial covers 10 doses, 2 weeks at 5-on/2-off. The 7-day reconstituted shelf life means low-dose users discard product significantly — at 0.5 mg/day from a 5 mg vial, only 6–7 doses fit within the stability window before discarding.

Reconstitution

Tesamorelin reconstitution differs meaningfully between pharmaceutical Egrifta SV and research-chemical tesamorelin, in ways that matter practically. Get the formulation you actually have right; the two are not interchangeable instructions.

Egrifta SV (pharmaceutical kit)

Egrifta SV ships as a kit: a vial of lyophilised tesamorelin (1.4 mg active, ~2 mg per the label conversion), a vial of sterile diluent (sterile water for injection — not bacteriostatic), and supplied syringes.3 5

Pharmaceutical procedure (per FDA label):

Reconstitute one vial of Egrifta SV with 0.5 mL of the supplied sterile diluent.
Roll the vial gently between your hands for 30 seconds. Do not shake.
Withdraw 0.35 mL into the supplied syringe and inject subcutaneously into the abdomen.
Discard any unused solution and the diluent vial immediately. The reconstituted Egrifta SV is single-use; do not refrigerate or save the leftover.

This is materially different from research-chem reconstitution. The pharmaceutical kit uses sterile water (no preservative), pre-measured to single-dose volumes, with no multi-day storage. Do not refrigerate Egrifta SV reconstituted solution.

Research-chemical tesamorelin (the off-label path)

Research-chemical tesamorelin ships as lyophilised white powder in a glass vial, typically 5 mg or 10 mg per vial. Reconstitution follows the same general convention as the rest of the GH cluster but with a much shorter stability window that constrains protocol planning.

You’ll also need:

Bacteriostatic water (BAC water) — sterile water with 0.9% benzyl alcohol. Required for any multi-day stability.
Insulin syringe (U-100) — 1 mL with 29G–31G needle.
A larger syringe (3 mL or 5 mL) for transferring BAC water into the vial.
Alcohol wipes, a clean working surface, somewhere to record what you did.

The math

5 mg vial, 1 mL BAC water

Concentration: 5 mg/mL
0.5 mg = 0.1 mL = 10 units
1 mg = 0.2 mL = 20 units
1.4 mg = 0.28 mL = 28 units (the per-vial dose in the Egrifta SV pharmaceutical kit)
2 mg = 0.4 mL = 40 units (the FDA-approved daily dose)

5 mg vial, 2 mL BAC water (for users wanting cleaner unit math at low doses)

Concentration: 2.5 mg/mL
0.5 mg = 0.2 mL = 20 units
1 mg = 0.4 mL = 40 units
2 mg = 0.8 mL = 80 units

10 mg vial, 2 mL BAC water (extends the per-vial dose count)

Concentration: 5 mg/mL
1 mg = 0.2 mL = 20 units
2 mg = 0.4 mL = 40 units
A 10 mg vial at 1 mg/day is 10 doses — but the 7-day shelf life means you’ll only use 5–7 doses before discarding the rest. Plan for product loss with low-dose protocols on this vial size.

The Peptrax Vial Plan calculator handles the same math interactively — enter your vial size, BAC volume, and dose, and it returns draw volume and doses per vial.

Reconstitution procedure (research-chem)

Wipe the rubber stopper of the lyophilised vial and the BAC water vial with alcohol.
Draw the chosen volume of BAC water into the larger syringe.
Insert the needle into the lyophilised vial at an angle, with the tip touching the inside wall above the powder. Inject the water slowly down the inside of the vial, not directly onto the powder. Forcing water onto lyophilised peptide can denature it.
Leave the vial undisturbed for 1–2 minutes. Do not shake. Gently swirl if needed; the powder dissolves on its own.
Once the solution is clear, label the vial: compound, concentration, reconstitution date.
Store refrigerated (2–8°C / 36–46°F).

Some practitioners pass the reconstituted solution through a 0.22 µm syringe filter as a belt-and-braces sterility step. Optional rather than standard.

Storage and stability

This is where tesamorelin diverges from the rest of the GH cluster. Reconstituted tesamorelin is meaningfully less stable than ipamorelin, CJC-1295, or sermorelin — the larger 44-residue peptide is more prone to aggregation and degradation in solution.

Conservative: 5–7 days refrigerated — the figure most research-chem vendors quote.
Middle: 7 days refrigerated — the most commonly cited figure across community sources.
Optimistic: ~14 days refrigerated — possible with strict cold-chain handling but not the typical research-chem reconstitution.

The honest middle is 7 days at 2–8°C. This is roughly a quarter of the shelf life of the other GH-cluster peptides and is the single biggest practical difference from a protocol-planning standpoint.

Store at the back of the refrigerator. Do not freeze.

If you reconstitute with plain sterile water instead of BAC water (matching the pharmaceutical Egrifta SV convention), the vial is single-use — discard within 24 hours, or in pharmaceutical practice, immediately after the single dose is drawn.

The stability constraint hits each protocol differently.

2 mg daily continuous (FDA-licensed protocol): a 10 mg vial is 5 doses → 5 days, well within shelf life. Buy 5 mg or 10 mg vials, finish quickly, reconstitute fresh.
1 mg daily, 5 on / 2 off (community protocol): a 5 mg vial is 5 weekly doses → 7 days at 5 doses/week, right at the edge. Plan vial timing carefully.
0.5 mg daily, 5 on / 2 off (sensitive start): a 5 mg vial is 10 doses but only 7 days of stability → discard ~30% of the vial. Smaller vials help if available.

What gets miscalculated

The recurring tesamorelin reconstitution errors:

Treating tesamorelin like ipamorelin or sermorelin for stability planning. The 7-day shelf life is a quarter of the rest of the cluster’s. Users who buy 10 mg vials for cost reasons and run them at low doses discard a meaningful fraction of the compound.
Mixing pharmaceutical and research-chem instructions. Egrifta SV uses sterile water, single-use, no refrigeration of reconstituted solution. Research-chem uses BAC water, ~7 days refrigerated. Mistakenly applying Egrifta SV’s “discard immediately” rule to research-chem product wastes compound; mistakenly storing pharmaceutical Egrifta SV reconstituted solution risks contamination.
mg vs mcg confusion. 1 mg = 1,000 mcg. Tesamorelin doses are in milligrams, unlike ipamorelin (mcg) — drawing 200 units thinking “200 mcg” delivers 1 mg if your concentration is 5 mg/mL.
Over-shaking the vial. Tesamorelin’s 44-residue size makes it more susceptible to aggregation from shaking than the smaller peptides in the cluster. Roll, don’t shake — this matters more for tesamorelin specifically.
Stacking with ipamorelin without reducing the tesamorelin dose. The community heuristic is −30%. Stacking at full doses of both produces larger GH/IGF-1 spikes than either monotherapy and, for sensitive users, more pronounced fluid retention.

Areas of concern ⚠

The off-label evidence gap

Tesamorelin’s strongest evidence is in HIV-associated lipodystrophy. The Phase 3 trials were designed for that population, the FDA approval is for that population, and the safety profile was characterised in that population. Off-label use in HIV-negative biohacker populations:

Has limited Phase 2 evidence (the obesity trial)
Has not been characterised at the community 1 mg / cycled dosing schedule
Operates outside the prescriber relationship the safety profile was developed within

This doesn’t mean tesamorelin doesn’t work in HIV-negative populations — the obesity trial suggests it does — but the evidence base is thinner for off-label use than for the licensed indication.

Long-term cardiovascular safety not established

The FDA prescribing information explicitly states this. The pivotal trials ran 26 weeks; longer-duration controlled outcome data does not exist. For users with CV risk factors, the absence of long-term data is the relevant uncertainty — not a known safety signal, but the absence of reassurance that semaglutide provides through SELECT or that tirzepatide is building through SURPASS-CVOT.

Cancer / IGF-1 / GH-axis concern (most acute in the GH cluster)

Tesamorelin produces the largest IGF-1 elevation of any compound in this cluster (81% in trials at 2 mg/day). The mechanistic concern about GH/IGF-1-driven mitogenicity for some tumour types applies most strongly here.

Treat as a relative contraindication for:

Active malignancy of any type
Recent (within ~5 years) malignancy of GH/IGF-1-responsive types — breast, prostate, colon, certain endocrine tumours
Multiple Endocrine Neoplasia syndromes
Strong family history of GH/IGF-1-responsive cancers without active screening in place

The FDA label includes corresponding warnings about active malignancy.

Glucose dysregulation

Tesamorelin produced modest but measurable increases in fasting glucose and HbA1c in the registrational trials, consistent with GH’s known counter-regulatory effect on insulin. The label includes a caution about monitoring glucose in diabetic and prediabetic patients. Users with insulin resistance, prediabetes, or active type 2 diabetes should track glucose markers and not assume “metabolic peptide” means metabolically benign for them.

Long-term safety beyond ~6 months is uncharacterised

Most controlled data is at 26 weeks. Multi-year safety in healthy users is unknown. Mechanistic concerns from sustained GH/IGF-1 elevation:

IGF-1 elevation theoretically mitogenic for tumour types
Insulin sensitivity shifts (documented modestly in the trials)
Pituitary feedback adaptation over months — the rationale for community cycling protocols, not directly studied

Quality and sourcing

For US patients with Egrifta SV/WR prescription: sourcing is the most robust of any GH-cluster compound — pharmaceutical-grade, supply-chain-verified, batch-tracked.

For UK users and US users on the research-chem path: standard research-chem caveats apply — no batch testing at point of sale, variable purity, no MHRA / FDA oversight. Tesamorelin’s 44-residue length makes it harder to synthesise at high purity than smaller peptides like ipamorelin (5 residues) or sermorelin (29 residues). Lab-tested vendors with explicit mass-spec certification matter more here than for shorter peptides.

Populations where tesamorelin is contraindicated or high-risk

Active or recent cancer history (relative contraindication; see above)
Active acromegaly or known pituitary adenoma
Pregnancy and breastfeeding — contraindicated per the FDA label
Type 1 diabetes — GH antagonises insulin; affects glycaemic control
Severe insulin resistance / poorly-controlled type 2 diabetes — same concern, smaller margin; monitor glucose
Sleep apnoea (untreated) — GH/IGF-1 effects on soft tissue may worsen airway collapse
Critical illness (e.g. ICU patients) — GH-axis stimulation is contraindicated in acute critical illness per general GH-class guidance
Hypersensitivity to mannitol or to any tesamorelin formulation excipient — per the FDA label

Measurement and dosing pitfalls

mg vs mcg confusion — tesamorelin doses are in mg, not mcg. A dose error here is much more impactful than for ipamorelin because the absolute mass is larger.
Reading “units” as mg. Units are a volume mark on the syringe.
Stability planning treating tesamorelin as a 28-day peptide. It’s a 7-day peptide. Plan vial size and dose schedule together.
Stacking with ipamorelin without dose adjustment. Reduce tesamorelin by ~30% when adding a GHRP.
Substituting research-chem tesamorelin for prescribed Egrifta SV without acknowledging the formulation differences. They’re not the same product; reconstitution and storage rules differ.

What the community gets wrong

“Tesamorelin is just a stronger sermorelin.” Pharmacologically related but mechanistically distinct (full-length GHRH(1-44) with hexenoyl modification vs GHRH(1-29) fragment). The outcome data is much stronger for tesamorelin specifically; the mechanism is not just “bigger version of sermorelin.”
“FDA approval means it’s safe for general anti-ageing use.” Approved for a specific narrow indication (HIV-associated lipodystrophy). Off-label use carries the broader uncertainty that comes with any off-label use of a licensed medicine.
“Visceral fat reduction means general fat loss.” The licensed indication and the trials specifically measured visceral adipose tissue (CT scan). Subcutaneous fat changes were modest. Tesamorelin is not a general weight-loss drug; it’s a visceral-fat-targeting drug.

FDA / regulatory status

Jurisdiction	Status	Last verified
US (FDA)	Approved. Egrifta (2010), Egrifta SV / F4 formulation (2019), Egrifta WR / F8 formulation (mid-2020s). Indication: reduction of excess abdominal fat in HIV-infected patients with lipodystrophy. Prescription only; dispensed through HIV specialty pharmacies. Off-label use is possible but is at prescriber discretion.	2026-04-29
UK (MHRA)	Not approved as a licensed medicine. No NHS or private-prescription pathway exists. Sold as a research chemical under “research use only / not for human consumption” labelling, which permits sale of the raw peptide but does not authorise human use.	2026-04-29
EU (EMA)	Not approved. No licensed product in EU markets.	2026-04-29
Canada	Approved. Tesamorelin is approved by Health Canada for the same indication as the FDA approval.	2026-04-29
WADA (sport)	Prohibited. Listed under S2 (Peptide Hormones, Growth Factors, and Related Substances). In and out of competition.	2026-04-29

Narrative. Tesamorelin’s regulatory pathway is the most legitimately licensed of any compound in the GH-axis cluster of this encyclopedia, but the licensed indication is narrow — HIV-associated lipodystrophy. For US users with HIV lipodystrophy, the licensed pathway is established and insurance-supported. For US users with other body-composition or metabolic goals, off-label prescribing is possible but rare and expensive. For UK users, there is no licensed pathway in any direction; research-chemical purchase remains the only access route, with the same legal grey area as the rest of this encyclopedia’s grey-market peptides.

For athletes: tesamorelin is on the WADA prohibited list. The IGF-1 elevation produces a measurable biomarker signature; out-of-competition testing can detect it.

What to track in Peptrax

“On tesamorelin” can mean three meaningfully different things: licensed 2 mg/day continuous (the FDA-approved Barth-syndrome / HIV-lipodystrophy protocol), community 1 mg/day with 5-on/2-off cycling (the dominant biohacker pattern), or sensitive-start 0.5 mg ramping. The dose-response curve is steep enough that these aren’t just dose variations — they produce different expected effects, side-effect risks, and vial-stability constraints. Capturing the protocol up front determines what counts as “working” and what counts as “tolerating.”

For most users, the highest-signal log is objective markers measured periodically: waist circumference (visceral fat proxy), morning fasting glucose if relevant, and IGF-1 every 8–12 weeks if accessible. Tesamorelin’s effects are slower and more biomarker-driven than ipamorelin’s or sermorelin’s — daily subjective tracking matters less than the 8-week snapshot. The Peptrax pattern that fits is “log the dose daily, take the measurement every 8 weeks, see what changed.”

For sensitive-systems users, the priority log shifts to the first 4 weeks of any new dose level: injection-site reactions, joint pain, water-retention symptoms (rings tighter, ankle swelling, hand puffiness), and morning glucose if you’re tracking it. Tesamorelin’s larger per-injection dose and IGF-1 elevation amplify these signals compared to GHRP-cluster compounds, so a written stop criterion and a slow ramp matter more here.

Across all users, reconstitution date is non-negotiable to log because the 7-day shelf life is much shorter than other GH-cluster compounds. Users who carry over tesamorelin reconstitution-date habits from ipamorelin or sermorelin (where 28 days is fine) will find themselves dosing from increasingly degraded vials. The app should flag the 7-day window automatically; the user should log the reconstitution event so the timer starts.

For personal tracking and informational purposes only — not medical advice.