Side-by-side · Research reference

HexarelinvsMT-1

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

APhase 1HUMAN-REVIEWED19/45 cited

BFDA-ApprovedHUMAN-REVIEWED9/51 cited

Hexarelin

Hexapeptide GHRP · Cardio-tropic

100–200 mcgPer doseSmith 1996

Phase 1Evidence levelGhigo 1997

~70 minHalf-lifeSemenistaya 2010

SQ · Multiple sites · 1–3×/day

MT-1

α-MSH Analogue · FDA-Approved

16 mgImplant dose

13 AAPeptide lengthChawathe 2026

2019FDA approval

SQ Implant · 60-Day Release

01Mechanism of Action

Parameter

Hexarelin

MT-1

Primary target

Ghrelin receptor (GHS-R1a) + cardiac CD36Smith 1996 Ghigo 1997

Melanocortin-1 receptor (MC1R) on melanocytesLangan 2010

Pathway

GHS-R1a → Gαq → Ca²⁺ → GH release. CD36 engagement → direct cardio-tropic actionGhigo 1997

α-MSH analogue → MC1R activation → cAMP elevation → MITF transcription → eumelanin synthesis

Downstream effect

Strong GH pulse + IGF-1 elevation; cardio-protective effects in animal MI modelsGhigo 1997

Increased melanogenesis, photoprotection, reduced UV sensitivityLangan 2010

Feedback intact?

Yes initially; tachyphylaxis with chronic useGhigo 1997

Yes — exogenous MC1R agonism does not suppress endogenous α-MSH production

Origin

Synthetic hexapeptide His-D-2-Methyl-Trp-Ala-Trp-D-Phe-Lys-NH₂Smith 1996

Synthetic 13-AA peptidomimetic with norleucine (position 4) and D-phenylalanine (position 7) substitutions for metabolic stabilityChawathe 2026

Antibody development

—

02Dosage Protocols

Parameter

Hexarelin

MT-1

Standard dose

100–200 mcg per injectionSmith 1996

16 mg subcutaneous implant

FDA-approved formulation (Scenesse).

Frequency

1–2× per day max (tachyphylaxis with chronic 3× daily)

Every 60 days

Sustained release implant — no daily administration required.

Lower / starter dose

50 mcg per dose

—

Evidence basis

Phase 1 / Phase 2 trialsSmith 1996 Ghigo 1997

Phase 3 RCT / FDA-approved orphan drug

Duration

4–8 weeks on / 4–8 weeks off (tachyphylaxis mitigation)

Seasonal use (spring–autumn typical)

Aligned with peak UV exposure months.

Reconstitution

Bacteriostatic water

—

Timing

Pre-sleep + fasted preferred

—

Half-life

~70 minSemenistaya 2010

—

Indication

—

Erythropoietic protoporphyria (EPP)

Narrow FDA approval — not licensed for cosmetic tanning.

Route

—

Subcutaneous implant — upper arm or abdomen

Stability

—

Norleucine/D-Phe substitutions enhance peptidase resistance

Modified structure vs endogenous α-MSH (Met⁴, L-Phe⁷).

04Side Effects & Safety

Parameter

Hexarelin

MT-1

Cortisol elevation

Modest at high dosesGhigo 1997

—

Prolactin elevation

Modest at high dosesGhigo 1997

—

Hunger

Strong appetite increase via ghrelin agonism

—

Tachyphylaxis

Receptor desensitisation with chronic dosingGhigo 1997

—

Cardiac effects

Direct cardio-tropic; potential benefit in MI but unstudied in humansGhigo 1997

—

IGF-1 elevation

Strong; monitor with chronic high-dose use

—

Cancer risk

Contraindicated in active malignancy (GH/IGF-1 axis)

—

Pregnancy / OB

Avoid

—

Nausea

—

Common (>10%) — mild, transient

Implant site reaction

—

Erythema, bruising, tenderness at insertion site

Hyperpigmentation

—

Generalised tanning (therapeutic effect), darkening of freckles/neviLangan 2010 Habbema 2017

Expected melanogenic response — complicates pigmented lesion surveillance.

Melanocytic changes

—

Rapid pigmentation of existing nevi; new melanocytic lesions reported with unregulated useHabbema 2017

Requires dermatologic monitoring; theoretical melanoma concern with chronic stimulation.

Headache

—

Occasional (MC1R-independent melanocortin effects)

Photosensitivity (paradoxical)

—

Rare phototoxic reactions despite melanin increase

Contamination risk (unregulated)

—

Impurity, infection, blood-borne virus transmission from illicit melanotan productsLangan 2010 Habbema 2017

Applies to internet/gym-sourced 'melanotan' — not FDA-approved Scenesse.

Absolute Contraindications

Hexarelin

·Active malignancy
·Pregnancy / breastfeeding
·Disrupted hypothalamic-pituitary axis

MT-1

·Hypersensitivity to afamelanotide or excipients
·Hepatic impairment (no safety data)
·Renal impairment (no safety data)

Relative Contraindications

Hexarelin

·Untreated diabetes
·Severe hyperprolactinemia

MT-1

·History of melanoma or atypical nevi (melanocortin receptor stimulation concern)Habbema 2017
·Pregnancy/lactation (insufficient data)
·Photosensitive dermatoses (other than EPP)

05Administration Protocol

Parameter

Hexarelin

MT-1

1. Reconstitution

Add 2 mL bacteriostatic water to 5 mg vial → 2.5 mg/mL = 250 mcg per 0.1 mL.

Performed by trained healthcare provider. Sterile technique. Small incision in upper arm (triceps) or lower abdomen using trocar. 16 mg rod (4 mm × 1.5 cm) inserted subcutaneously.

2. Injection site

SQ — abdomen or thigh. Rotate sites.

Pressure applied post-insertion. Sterile dressing × 24 hrs. Avoid strenuous activity for 24–48 hrs to prevent extrusion.

3. Timing

Pre-sleep + fasted preferred. Cycle on/off to avoid tachyphylaxis.

Slow biodegradable polymer matrix releases afamelanotide over 60 days, maintaining therapeutic plasma levels without daily dosing.

4. Storage

Lyophilised: room temp, light-protected. Reconstituted: refrigerate ≤30 days.

New implant every 60 days during high UV season (spring–autumn in temperate climates). Rotate implant sites to avoid scarring.

5. Needle

29–31G, 4–8 mm insulin syringe.

Baseline and periodic dermatologic exams to document pigmented lesions. Patient education on self-examination for new/changing nevi.

06Stack Synergy

Hexarelin

+ CJC-1295 (no DAC)

Strong

View CJC-1295 (no DAC) →

Hexarelin (GHRP) + CJC-1295-no-DAC (GHRH analogue) is the higher-amplitude variant of the standard GHRH+GHRP stack. Hexarelin produces a stronger pulse than ipamorelin but with cortisol + prolactin signal — choose this stack for maximum GH amplitude when side-effect tolerance is acceptable. Cycle aggressively.

Hexarelin: 100 mcg SQ · pre-sleep
CJC-1295 (no DAC): 100 mcg SQ · same injection
Primary benefit: Maximum GH pulse amplitude (with side-effect signal)

Smith 1996 Teichman 2006

MT-1

— no documented stacks