Side-by-side · Research reference

GHRP-6vsThymosin α-1

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

APhase 1Reviewed10/36 cited

BPhase 3Reviewed8/39 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

Thymosin α-1

Immune modulator · Approved (some countries)

1.6 mgPer doseIyer 2007

Phase 3Evidence levelIyer 2007 Camerini 2001

~2 hrHalf-life

SQ · 2× weekly · 6+ months for chronic indications

01Mechanism of Action

Parameter

GHRP-6

Thymosin α-1

Primary target

Ghrelin receptor (GHS-R1a)Bowers 1990

Toll-like receptor 9 (TLR9) + T-cell maturation pathwayCamerini 2001

Pathway

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

TLR9 activation → ↑ IFN-α + IL-2 + IFN-γ → enhanced T-cell function + dendritic cell maturationIyer 2007

Downstream effect

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

Restored T-cell function, improved viral clearance, anti-tumour adjuvant effectsIyer 2007

Feedback intact?

—

Origin

Synthetic hexapeptide; first-generation GHRP from Bowers groupBowers 1990

Synthetic 28-AA peptide identical to natural Tα-1 isolated from thymus extractCamerini 2001

Antibody development

—

02Dosage Protocols

Parameter

GHRP-6

Thymosin α-1

Standard dose

100–200 mcg per injectionBowers 1990

—

Frequency

1–3× per day

2× weekly (Mon/Thu typical)

Lower / starter dose

50 mcg per dose

0.8 mg per injection

Evidence basis

Phase 1 + clinical practiceBowers 1990

Phase 3 + approved (35+ countries as Zadaxin)Iyer 2007

Duration

8–12 weeks on / 4 off

6–12 months for chronic indications

Reconstitution

Bacteriostatic water

Sterile water for injection per vial label

Timing

Pre-meal preferred for appetite support

No specific time

Half-life

~15 minMalagón 1999

~2 hours plasma; tissue effect days

Standard dose (HBV/HCV)

—

1.6 mg SQ 2× weekly × 6–12 monthsIyer 2007

04Side Effects & Safety

Parameter

GHRP-6

Thymosin α-1

Hunger

Pronounced — defining feature vs ipamorelin

—

Cortisol elevation

Mild

—

Prolactin elevation

Mild

—

Injection site reaction

Mild

Erythema, mild discomfort

Cancer risk

Contraindicated in active malignancy

No signal — used as adjuvant in oncology

Pregnancy / OB

Avoid

GI symptoms

—

Rare nausea

Fatigue

—

Common during initial weeks

Fever / flu-like

—

Mild interferon-like response possible

Autoimmune

—

Theoretical risk; caution in active autoimmune disease

Absolute Contraindications

GHRP-6

·Active malignancy
·Pregnancy / breastfeeding

Thymosin α-1

·Pregnancy / breastfeeding
·Hypersensitivity to peptide
·Concurrent immunosuppressant therapy (transplant patients)

Relative Contraindications

GHRP-6

·Severe insulin resistance (appetite-driven caloric load)

Thymosin α-1

·Active autoimmune disease
·Severe immunocompromised state without supervision

05Administration Protocol

Parameter

GHRP-6

Thymosin α-1

1. Reconstitution

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

Add 1 mL sterile water per 1.6 mg vial → 1.6 mg/mL.

2. Injection site

SQ — abdomen. Rotate sites.

SQ — abdomen, thigh, or upper arm. Rotate sites.

3. Timing

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

2× weekly, e.g. Monday + Thursday.

4. Storage

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

Lyophilised: refrigerate. Reconstituted: refrigerate, use within 24 h.

5. Needle

29–31G, 4–8 mm insulin syringe.

27–31G, 4–8 mm insulin syringe.