Sermorelin vs tesamorelin
Both are lab-made versions of growth-hormone-releasing hormone (GHRH). Tesamorelin is an approved drug with large trials; sermorelin was approved for children until it was discontinued in 2008.
- Sermorelin
- Human studiesOnce nightly
- Tesamorelin
- Approved drugOnce daily
- Head-to-head trials
- None published
The short answer
Sermorelin is the first 29 amino acids of GHRH. Tesamorelin is the full 44-amino-acid hormone with a stabilizing group added at the front. Both prompt the pituitary to release its own growth hormone, and both are injected once a day.
Tesamorelin (Egrifta) is FDA-approved to reduce excess belly fat in adults with HIV-associated lipodystrophy, based on trials in about 800 people. Sermorelin (Geref) was approved for growth hormone deficiency in children and discontinued in 2008, and FDA later found that wasn’t for safety or effectiveness reasons. Its human data come mostly from children and small studies in older men.
At a glance
| Field | SermorelinGRF 1-29, formerly Geref | TesamorelinEgrifta SV, Egrifta WR |
|---|---|---|
| Evidence | Human studies | Approved drug |
| Class | GHRH analog | GHRH analog |
| Approval | Formerly approved in the US as Geref (diagnostic, 1990; GH deficiency in children, 1997). Discontinued in 2008, not for safety or effectiveness reasons. | Approved in the US as Egrifta WR and Egrifta SV, to reduce excess abdominal fat in adults with HIV and lipodystrophy. |
| Sport (WADA 2026) | Banned in sport | Banned in sport |
| Common dose | 200–300 mcg nightly | 1–2 mg daily |
| Frequency | Once nightly | Once daily |
| Cycle | No set cycle | Continuous |
| Route | Subcutaneous injection | Subcutaneous injection (abdomen) |
| Half-life | about 6 to 7 minutes Label | about 8 to 11 minutes Label |
| Typical draw | 10 units5 mg with 2.5 mL, 200 mcg | 40 units10 mg with 2 mL, 2 mg |
| Vial sizes or form | 5, 10 mg | 5, 10, 20 mg |
| Human studies | 5 listedLargest: 110 people (1996) | 5 listedLargest: 806 people (2010) |
| Main cautions |
|
|
| Open Sermorelin | Open Tesamorelin |
Doses shown are what labels, trials or community reports reference, not recommendations. Each compound’s page has the full detail and sources.
Key differences
Structure
Sermorelin: 29 amino acids (GRF 1-29). Tesamorelin: all 44 amino acids of GHRH, with a hexenoyl group added to stabilize it.
Approval
LabelTesamorelin: approved in the US as Egrifta WR (1.28 mg) and Egrifta SV (1.4 mg). Sermorelin: approved in 1990 for testing and in 1997 for children with growth hormone deficiency; discontinued in 2008.
Human evidence
TrialTesamorelin: Phase 3 trials in 806 people with HIV; visceral fat fell about 15% more than on placebo at 26 weeks, and IGF-1 rose. Sermorelin: open-label studies in children (growth rate nearly doubled at 6 months) and small studies in older men, one of which raised GH without changing IGF-1 or body composition.
Doses
Tesamorelin: 1.28 or 1.4 mg once a day, depending on the product (label). Sermorelin: 30 mcg/kg at bedtime in children (former label); adults use 200–300 mcg nightly (community).
Half-life
LabelBoth are short: sermorelin about 6 to 7 minutes after IV injection, tesamorelin 8 to 11 minutes after injection under the skin.
Side effects
LabelTesamorelin’s label lists injection-site reactions (25% vs 14% on placebo), joint pain, swelling, numbness and higher blood sugar. Sermorelin’s former label lists injection-site pain (about 1 in 6) and brief flushing.
Head-to-head studies
Taking them together
Sermorelin and tesamorelin both act on the same receptor (the GHRH receptor), so they double up rather than add a different effect.
Source: Egrifta and Geref labels; WADA 2026 list, S2.2.4
Sermorelin and tesamorelin each raise growth hormone or IGF-1 activity. Tesamorelin’s label advises monitoring IGF-1 and lists fluid retention, joint pain and higher blood sugar as side effects.
Source: Egrifta prescribing information
Open them in the stack check for sport status and one combined tracking checklist.
Questions
What is the difference between sermorelin and tesamorelin?
Sermorelin is the first 29 amino acids of GHRH. Tesamorelin is the full 44-amino-acid hormone with a stabilizing group added at the front. Both prompt the pituitary to release its own growth hormone, and both are injected once a day.
Is tesamorelin stronger than sermorelin?
No trial has compared them, so there’s no measured answer. Tesamorelin has the stronger evidence: placebo-controlled trials in about 800 adults showing less belly fat and higher IGF-1. Sermorelin’s adult data are small studies, one of which raised GH without changing IGF-1 or body composition.
Can sermorelin and tesamorelin be taken together?
The stack check flags two GHRH analogs and several growth hormone compounds. Sermorelin and tesamorelin both act on the same receptor (the GHRH receptor), so they double up rather than add a different effect. Sermorelin and tesamorelin each raise growth hormone or IGF-1 activity. Tesamorelin’s label advises monitoring IGF-1 and lists fluid retention, joint pain and higher blood sugar as side effects. No published study has tested them together.
Which has more evidence in people, sermorelin or tesamorelin?
Sermorelin was approved in the US in the past; its page lists 5 key human studies. Tesamorelin is approved in the US; its page lists 5 key human studies. They haven’t been compared directly in a published trial.
Are sermorelin and tesamorelin banned in sport?
Sermorelin and tesamorelin are banned at all times. This follows the WADA 2026 Prohibited List; athletes should confirm with their anti-doping organization.
Sources
- Egrifta WR and Egrifta SV labels (DailyMed)
- Federal Register: Geref not withdrawn for safety reasons (2013)
- Falutz et al., pooled Phase 3 tesamorelin trials (J Clin Endocrinol Metab 2010) PMID 20554713
- Thorner et al., sermorelin in children with GH deficiency (J Clin Endocrinol Metab 1996) PMID 8772599
- Vittone et al., sermorelin in older men (Metabolism 1997) PMID 9005976
Each compound’s page lists its full sources: Sermorelin, Tesamorelin.