Side-by-side · Research reference

GHRP-6vsTesamorelin

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

APhase 1Reviewed10/36 cited

BFDA-ApprovedVerified27/68 cited

GHRP-6

Hexapeptide GHRP · Strong appetite stimulant

100–200 mcgPer doseBowers 1990

Phase 1Evidence levelBowers 1990

~15 minHalf-lifeMalagón 1999

SQ · Multiple sites · 1–3×/day

Tesamorelin

GHRH Analogue · FDA-Approved

2 mgDaily doseEGRIFTA® (tesamorelin for inje 2010

15–20%VAT reductionFalutz 2010

~26 minHalf-lifeEGRIFTA® (tesamorelin for inje 2010

SQ · Abdomen · Once Daily

01Mechanism of Action

Parameter

GHRP-6

Tesamorelin

Primary target

Ghrelin receptor (GHS-R1a)Bowers 1990

Hypothalamic GHRH receptorsEGRIFTA® (tesamorelin for inje 2010

Pathway

GHS-R1a → Gαq → Ca²⁺ → GH release; central appetite driveBowers 2002

GHRH → Pituitary GH release → Liver IGF-1 synthesisFalutz 2007

Downstream effect

GH pulse + strong appetite stimulation; modest IGF-1 elevationBowers 2002

Increased GH pulsatility, elevated IGF-1, lipolysis of visceral adipose tissueFalutz 2010

Feedback intact?

—

Yes — physiological pulsatility preserved

Origin

Synthetic hexapeptide; first-generation GHRP from Bowers groupBowers 1990

Synthetic 44-AA GHRH analogue with trans-3-hexenoic-acid modification for stabilityEGRIFTA® (tesamorelin for inje 2010

Antibody development

—

~50% after 26 wks (non-neutralising in most)Sévigny 2018

02Dosage Protocols

Parameter

GHRP-6

Tesamorelin

Standard dose

100–200 mcg per injectionBowers 1990

2 mg / dayEGRIFTA® (tesamorelin for inje 2010

FDA-approved protocol.

Frequency

1–3× per day

Once daily (morning or pre-sleep)

Aligns with natural GH pulse.

Lower / starter dose

50 mcg per dose

1 mg / dayFalutz 2010

1 mg still produces significant IGF-1 elevation.

Evidence basis

Phase 1 + clinical practiceBowers 1990

RCT / FDA-approvedFalutz 2007 Falutz 2010

Duration

8–12 weeks on / 4 off

12–52 weeks

VAT returns within months of stopping.

Reconstitution

Bacteriostatic water

Sterile water per labeling

Preserved at 2–8 °C after reconstitution.

Timing

Pre-meal preferred for appetite support

Empty stomach, pre-sleep preferred

Half-life

~15 minMalagón 1999

~26 min (plasma)EGRIFTA® (tesamorelin for inje 2010

Modified vs native GHRH (7 min t½).

03Metabolic / Fat Loss Evidence

Parameter

GHRP-6

Tesamorelin

Primary fat target

—

Visceral adipose tissue (VAT) — abdominal

Quantified reduction

—

15–20% VAT ↓Falutz 2010

By CT at 26 weeks (Falutz et al., NEJM).

IGF-1 impact

—

+66 ng/mL (2 mg dose) · +81% mean elevationFalutz 2007

Effect on lean mass

—

Modest lean mass preservation / slight increase

Insulin sensitivity

—

Neutral to slight impairment (monitor HbA1c)Clarke 2018

Triglycerides

—

Significant TG reduction noted in Phase 3Falutz 2010

Glucose metabolism

—

Generally neutral; 4.5% HbA1c elevation riskClarke 2018

Effect reversibility

—

VAT returns within months of stopping

Key publication

—

Falutz et al. NEJM 2007 · Falutz JCEM 2010 · FDA approval 2010Falutz 2007 Falutz 2010 EGRIFTA® (tesamorelin for inje 2010

04Side Effects & Safety

Parameter

GHRP-6

Tesamorelin

Hunger

Pronounced — defining feature vs ipamorelin

—

Cortisol elevation

Mild

—

Prolactin elevation

Mild

—

Injection site reaction

Mild

Erythema, pruritus, redness (common)

Cancer risk

Contraindicated in active malignancy

Contraindicated in active malignancy (GH/IGF-1 axis); theoretical tumour growth riskEGRIFTA® (tesamorelin for inje 2010

Pregnancy / OB

Avoid

ContraindicatedEGRIFTA® (tesamorelin for inje 2010

Fluid retention / Edema

—

Peripheral edema, arthralgia, carpal tunnel (GH-axis effect)

Glucose intolerance

—

HbA1c ↑ in 4.5% vs 1.3% placebo; HbA1c ≥6.5% hazard OR 3.3Clarke 2018

IGF-1 elevation

—

Dose-dependent; supraphysiological levels = discontinue

Antibody formation

—

~50% at 26 weeks; non-neutralising in most; rare hypersensitivity (<1%)Sévigny 2018

GI symptoms

—

Nausea, diarrhea (mild, transient)

Absolute Contraindications

GHRP-6

·Active malignancy
·Pregnancy / breastfeeding

Tesamorelin

·Active malignancy or history of treated cancer
·Pregnancy
·Hypersensitivity to tesamorelin or mannitol
·Disruption of hypothalamic-pituitary axis (trauma, tumour, radiation)

Relative Contraindications

GHRP-6

·Severe insulin resistance (appetite-driven caloric load)

Tesamorelin

·Untreated diabetes (monitor HbA1c)
·Severe carpal tunnel syndrome
·Acute critical illness

05Administration Protocol

Parameter

GHRP-6

Tesamorelin

1. Reconstitution

Add 2 mL bacteriostatic water to 5 mg vial → 2.5 mg/mL.

Add 2.1 mL sterile water to 2 mg lyophilised vial. Roll gently — do not shake. Solution should be clear.

2. Injection site

SQ — abdomen. Rotate sites.

Subcutaneous — abdomen preferred. Rotate sites (avoid same spot within 2 cm). Avoid navel and waistband area.

3. Timing

Pre-meal for appetite support; pre-sleep for GH alignment.

Once daily. Preferred: evening, 2–3 hrs post-meal, before sleep — aligns with natural GH secretion pulse.

4. Storage

Lyophilised: room temp. Reconstituted: refrigerate ≤30 days.

Lyophilised: room temp, light-protected. Reconstituted: refrigerate 2–8 °C, use within 21 days.

5. Needle

29–31G, 4–8 mm insulin syringe.

27–31G, 4–8 mm insulin syringe. Pinch skin, 45° angle for lean individuals.

06Stack Synergy

GHRP-6

— no documented stacks

Tesamorelin

+ Ipamorelin

Strong

View Ipamorelin →

Tesamorelin (GHRH analogue) and ipamorelin (GHRP / ghrelin mimetic) act on two distinct receptor systems to amplify GH release synergistically — GHRH receptor + ghrelin receptor. This dual-axis stimulation produces a more robust, sustained GH pulse than either alone while maintaining physiological pulsatility. Ipamorelin is highly selective with minimal cortisol or prolactin elevation, making it the preferred GHRP pairing.

Tesamorelin: 2 mg SQ · evening
Ipamorelin: 200–300 mcg SQ · same injection
Frequency: Once daily, pre-sleep
Primary benefit: Maximal GH pulsatility, fat loss, recovery, sleep quality

Raun 1998