After approximately 7 months of using tesamorelin, I experienced a severe reaction consistent with anaphylaxis immediately after injecting it.
Bad reactionInjection · ~7 months
several peptides used alongside, sometimes on the same day
Strict case
GH/IGF-1 axis elevation (neoplasm and glucose warnings on label) plus anaphylaxis reports.
Users report
Gradual visceral-fat loss (several DEXA-confirmed, 40%+ in one case), much better sleep and muscle retention during GLP-1 cuts, with results taking 4-8+ weeks. Sceptics note that most visible results come from retatrutide, and a minority see nothing, especially when already lean. Water retention (sometimes numb or tingling hands), joint pain, disturbed sleep or a raised night heart rate, and itchy injection-site welts are common. Anaphylaxis accounts recur throughout 2026, typically after months of use and often after weeks of worsening welts. They include ER and hospital visits, loss of consciousness, and one reaction masked by daily antihistamines. A separate account describes a week in hospital with reactive hypoglycaemia (glucose below 40) on tesamorelin plus ipamorelin.
Best effects
Visceral fat reduction · better sleep · muscle preservation in a deficit · IGF-1 rise without shutting down endogenous GH
Raises GH/IGF-1: label warns on neoplasm (contraindicated with active malignancy) · Glucose intolerance / diabetes risk · Hypersensitivity incl. anaphylaxis (label + multiple user reports)
Evidence
Approved drug — approved in US (HIV-associated lipodystrophy)
Typical use
1-2 mg/day subQ at night, 5 days on / 2 off for 12 weeks. Users report 1–1.4 mg/day (median 1.4 mg, n=5).
Getting it
FDA-approved as Egrifta WR (and SV) only for HIV-associated abdominal fat; some US clinics prescribe it off-label or compounded. Most Reddit users buy research-peptide vials.
Stacked with
Retatrutide or tirzepatide: The dominant pairing, meant to protect muscle and target visceral fat during a GLP-1 cut. Sceptics say the GLP-1 does most of the visible work. · Ipamorelin: Sold as a premixed tesa/ipa blend for sleep and recovery. Several anaphylaxis posters later reacted to CJC/ipamorelin or sermorelin too. · HGH: A common next step after tesamorelin, chosen for cost or after an allergic reaction.
I’m on the same protocol, 2mg at bedtime, 5/2. I’m on Reta also, so after a 6pm dinner I no longer snack. 7 months in, 4 inches off my waist. Love handles and back fat greatly reduced.
Glowing2 mg at bedtime, 5 on/2 off · Injection · 7 months
I ran a 12 week cycle for Tesa/Ipa and went from 18% body fat to 14.3%. They worked for me. Obviously there were other variables, diet, sleep, alcohol intake, gym schedule etc.
Extraordinary sleep. At 1mg I overshot my IGF1, so I had to dial it back to 0.6mg. Decimated lower ab fat. I had some pain in my shoulders each morning, I assume GH related.
I added tesa just over 4 weeks ago. I’ve had a marked reduction in both the belly lump and gynecomastia while losing 6 lbs in that time. The weight loss is in line with what I’ve been losing on tirz, but where it came off has obviously changed.
I had a solid 4 pack, working on a 6 pack when I started tesamorelin, and 2 months later my abs were barely visible because the visceral fat I lost was pushing my ab muscles out from behind.
I started Tessa 500 µg for the first five days and then the following week I went to 1 mg and towards the end of the week I start getting really bad back pain and neck pain.
Noticed a slight improvement in visceral fat reduction and sleep quality but for the $ I could have just worked harder in the gym and slept a little more.
I took it for 10 weeks and very happy with the results. I have visible abs again at age 45! I started getting numb tingly hands/fingers in the middle of the night so stopped a bit short of a 12 week cycle.
I’ve been on Tessa for four days now, and my sleep has been incredibly poor. My resting heart rate variability (HRV) is significantly low, and my resting heart rate is elevated by 10 beats.
NegativeSleep · 1 mg, 2 h after last meal · 4 days
The frustrating part is that I was in really good shape before starting. Now, despite still being lean underneath, I just look and feel a lot bulkier and softer from all the extra water.
When paramedics arrived, they checked my blood sugar and it was below 40 (which is life threatening). At the hospital I was diagnosed with reactive hypoglycemia and stayed for about a week.
Bad reaction2 mg/day · 3 weeks
also ipamorelin 500 mcg each morning; low-carb diet before the event
Immediately after injection, heat traveled through my body, my palms turned red and my lips and tongue itched. I barely made it to the couch before my heart rate spiked into the 170’s and I lost consciousness.
Bad reactionInjection
rural, EMS over an hour away; now carries an EpiPen
I've been taking Tesamorelin 0.5 mg daily (Monday–Friday) without any issues. Today I decided to increase my dose to 1 mg, and within a short time my entire body became incredibly itchy.
Bad reaction0.5 mg raised to 1 mg · ~3 months
also on retatrutide, GHK-Cu and MOTS-c; settled with loratadine
I was completely fine for about six months, then one night after injecting, my fingers started itching, followed by my tongue and throat. Thankfully, it wasn't severe enough to require a hospital visit.
Bad reaction2 mg · ~6 months
also on GHK-Cu and BPC-157; switched to GH
Safety
Tier by safety barStrict ExcludedBalanced ExcludedEvidence only Excluded
A GHRH analogue that raises IGF-1, above 2 SDS in 47% of patients at 26 weeks; the label states the effects of prolonged IGF-1 elevation are unknown and requires any malignancy to be inactive. Egrifta WR (tesamorelin) US prescribing information, 2025 ↗
Active cancer or a history of cancer · Disrupted hypothalamic-pituitary axis (hypophysectomy, pituitary tumour or surgery, head irradiation) (label) · Diabetes or impaired glucose tolerance · Pregnancy (label)
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Report grades
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GlowingPositiveMixedNothingNegativeBad reaction
% positive
The share of a peptide's graded Reddit and X reports that are glowing or positive, vendor-adjacent posts left out. A peptide with few reports is pulled toward the average of all reports, as if it had eight average ones besides its own, so two glowing posts cannot top the list. Kept peptides rank by the same reports' mean grade, shrunk the same way, and excluded ones follow in that order.
Researcher estimate
No first-hand report of this peptide has been graded yet, so the figure is the researchers' own rating out of 10 from what they read about it. It ranks alongside the computed scores until reports arrive.
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Each peptide is tiered clean, caution or excluded from its five risk axes under the chosen safety bar. An excluded peptide has a plausible route to serious harm, so it stays listed with the reason but ranks behind every other entry, however good its reviews.
Safety bar
The safety bar sets how much risk it takes to exclude a peptide. Strict: out on any serious mechanism with little human data, or any documented serious harm. Balanced: out on documented serious harm (unless it is obvious, reversible and from a regulated product), or a serious mechanism whose harm would be silent with no human data at all. Evidence only: out only on documented serious harm in humans that is lasting, delayed or from grey-market product.
Seen harm
Documented serious adverse events in humans, from 0 for none despite real exposure to 3 for deaths or several well-documented serious harms. Serious means a hospital or emergency visit or harm lasting weeks, so a headache or a bad night does not count.
Mechanism
A plausible biological route to serious harm at the doses people use, such as growth-factor signalling, hormone-axis suppression, heart or blood-pressure effects or immune activation. It runs from 0 when none is known to 3 when a dangerous pathway has been shown in living animals.
Data gap
How little human safety data exists for the molecule actually sold, from 0 for an approved drug with large trials and years of use to 3 for no human safety data at all. A modified analogue does not inherit its parent's trials.
Silent harm
Whether the feared harm would show quickly or stay hidden, from 0 when it is obvious and goes on stopping to 3 when it is silent and delayed, like tumour promotion or slow organ damage. User reports cannot reveal a harm that takes years to appear, so a high score here limits what good reviews can tell you.
Product
The risk of what people actually buy, from 0 for a regulated pharmacy or supplement product taken by mouth or on the skin to 3 for a grey-market injectable. In one dataset of 6,441 grey-market samples, 42–71% failed basic quality criteria and 15% carried endotoxin.
Evidence
The strongest kind of study behind the peptide's effects, from an approved drug through human controlled trials and small human studies to animal work or nothing of its own. Animal results often fail to carry over to people.
Access
How people get it: as an approved drug, a compounded prescription, an over-the-counter supplement or from the grey market, where nobody checks the vial. The channel decides both the legal position and the risk of a bad batch.
Price per month
Thirty days of the typical dose, from its low end to its high end, priced at the listing a careful buyer would choose: in stock, from a shop scoring 4 of 5 on trust (third-party tested where no score is set), failing that 3, a pure pack before a blend, a European shop first, then the cheapest per mg. The range is the dose's, not the shops'. A per-dose amount counts once a day unless the dose says otherwise. Prices are in euros at ECB rates of 2026-10-29, before shipping; the shop table keeps each listing's price per mg, per gram for bulk supplements. Where no listing can be priced the researchers' own estimate stands in, and says so.
Dose users report
The middle half of the daily doses stated in at least five first-hand reports, vendor posts left out. Where its middle sits more than twice above or below the declared dose, the month is priced at it as well, since what people take is what they pay for.
Testing
Whether the shop publishes lab results: third-party tested means an independent lab checks each batch, own COA means the shop's own certificate of analysis, and no public tests means neither. A certificate shows purity, not safety.
Added peptide
Some packs sold under one peptide's name hold a second one, such as 5 mg GHK-Cu in a nasal kit, stated only in the description. Sprayed in the nose or injected it reaches the blood like an injection, so it carries the risk of that route and is tiered as the injectable form, whatever its tier on the skin. A pack whose page gives no contents list may hold more than its name.