Half-lifeAbout 11 minutes for Egrifta WR (FDA label); its effect on IGF-1 lasts much longer with daily use
Vial sizes2 mg, 5 mg, 10 mg, 11.6 mg
The simple version
What it does
It shrinks the deep fat around your organs by boosting your own growth hormone.
How people take it
2 mg as a shot under the skin of the belly, once a day.
Know this
It can raise blood sugar, so get it checked before and during use.
What it is
Tesamorelin is a lab-made copy of the brain signal that tells your body to release growth hormone, tweaked to last longer. It is the only drug of its type the FDA has approved, sold as Egrifta for one job: cutting the deep belly fat some people with HIV build up on certain HIV medicines. It comes in two versions, Egrifta SV (a 2 mg vial, 2 mg a day) and Egrifta WR (approved March 2025, an 11.6 mg vial mixed once a week, 1.28 mg a day), which give similar blood levels but are not swapped one-for-one.
How it works
It tells your pituitary, a small gland under your brain, to release more of your own growth hormone. That makes your body burn the deep fat packed around your organs, not the fat under your skin, and it also lowered liver fat in trials. The scale barely moves, but the fat inside your belly shrinks.
FDA-approved for: Reducing excess belly (visceral) fat in adults with HIV-associated lipodystrophy (2010)
What people use it for
Deep belly fat in people with HIV-related fat buildup (the approved use)
Liver fat (studied in people with HIV)
Off-label: belly fat and body shape in people without HIV
The evidence
FDA-approved
Strong for its approved use: two big trials in people with HIV found about 15% less deep belly fat after 26 weeks, plus lower blood fats (triglycerides), and later trials found less liver fat and slower fatty liver disease. The fat came back after people stopped. It hasn't been well tested in people without HIV, long-term heart safety isn't known, and it is not a weight-loss drug.
Any consistent time; inject into the belly, rotating sites
Cycle
Ongoing. Reassess if visceral fat has not dropped after about 26 weeks.
Route
Subcutaneous injection (abdomen)
Why: This is the dose used in the big trials. Your body clears it in minutes. But its effect on growth hormone builds up when you take it every day.
FDA label: Egrifta WR (11.6 mg vial)
Label dose
Dose
1.28 mg (0.16 mL of the mixed vial)
How often
Once a day
When
Any consistent time; inject into the belly, rotating sites. One mixed vial lasts 7 days.
Cycle
Ongoing, same as above
Route
Subcutaneous injection (abdomen)
Why: This newer version reaches the same blood levels as 2 mg of the original, at a lower dose. You can't swap it one-for-one with the 2 mg version.
Off-label (clinic/community)
Reported
Dose
1–2 mg
How often
Once a day, sometimes 5 days on and 2 off
When
Often before bed on an empty stomach, or in the morning fasted
Cycle
Often 12–26 weeks, with IGF-1 and blood sugar checks
Route
Subcutaneous injection (abdomen)
Why: People without HIV borrow the label dose to target belly fat. Bedtime or empty-stomach dosing is meant to line up with your natural nighttime growth hormone boost and keep insulin from dulling it. The label doesn't require this.
Start at the low end, and change one thing at a time. If you take medication or have a health condition, check with a doctor first.
Pregnant (the label says never: it can harm the baby; stop if you get pregnant)
Active cancer; any past cancer must be fully treated and inactive first
Damage to the hypothalamus or pituitary, the brain's hormone control centers (from surgery, radiation, a tumor or a head injury)
Allergy to tesamorelin or mannitol
Serious sudden illness (growth hormone raised death rates in critically ill patients)
Diabetes or prediabetes, unless a doctor is tracking your blood sugar
Diabetes-related eye damage (retinopathy)
Interactions
Insulin and diabetes meds: doses may need changing because blood sugar can rise
Steroid replacement for weak adrenal glands: you may need a higher dose after starting
Drugs your liver breaks down with CYP450 enzymes (like some seizure drugs, cyclosporine and steroids): growth hormone can change their levels, so watch closely
Get help right away for swelling of the face or throat, trouble breathing, chest pain, or a spreading, hot, red injection site.
Storage & legal
Storage
Egrifta WR: room temperature before and after mixing; use within 7 days of mixing. Egrifta SV: follow the package insert. Research-grade powder: fridge. Once mixed, keep it in the fridge and use within about 2–3 weeks.
Legal status
FDA: FDA-approved by prescription (Egrifta, first approved 2010; Egrifta SV 2 mg; Egrifta WR 1.28 mg approved March 2025) only for excess belly fat in adults with HIV lipodystrophy. Any other use is off-label.
Sport (WADA): Prohibited at all times (S2, growth hormone-releasing factors). Tesamorelin is named on the list.
Why are there two different FDA doses (2 mg and 1.28 mg)?
They're two different formulas. The newer one (Egrifta WR) absorbs better, so 1.28 mg gives you the same amount as 2 mg of the older one. Don't swap doses between them.
Will tesamorelin make me lose weight?
Probably not on the scale. The label calls it weight-neutral. It goes after the deep fat around your organs, which you might notice as a smaller waist.
What blood tests matter?
Fasting blood sugar or HbA1c (a 3-month sugar average) before and during use, plus IGF-1, a marker of growth hormone. The label tells doctors to check IGF-1 and think about stopping if it stays high.
What happens when I stop?
In the trials, the belly fat came back after people stopped. The benefit only lasts while you keep taking it.
Sources
EGRIFTA WR (tesamorelin) for injection. FDA prescribing information, revised 3/2025. Source
Falutz J, et al. Metabolic effects of a growth hormone-releasing factor in patients with HIV. N Engl J Med. 2007;357(23):2359-70. PubMed 18057338
Falutz J, et al. Effects of tesamorelin (TH9507), a growth hormone-releasing factor analog, in human immunodeficiency virus-infected patients with excess abdominal fat: a pooled analysis of two multicenter, double-blind placebo-controlled phase 3 trials with safety extension data. J Clin Endocrinol Metab. 2010;95(9):4291-304. PubMed 20554713
Stanley TL, et al. Effect of tesamorelin on visceral fat and liver fat in HIV-infected patients with abdominal fat accumulation: a randomized clinical trial. JAMA. 2014;312(4):380-9. PubMed 25038357
Stanley TL, et al. Effects of tesamorelin on non-alcoholic fatty liver disease in HIV: a randomised, double-blind, multicentre trial. Lancet HIV. 2019;6(12):e821-e830. PubMed 31611038