Side-by-side · Research reference

BPC-157vsRetatrutide

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

APhase 2Reviewed9/53 cited

BPhase 2Reviewed10/41 cited

BPC-157

Stable Gastric Pentadecapeptide · Healing

250–500 mcgDaily doseHwang 2016

Phase 2Evidence levelHwang 2016 Sikiric 2018

~30 minHalf-life (est.)

SQ or IM · Local · Once or twice daily

Retatrutide

Triple-receptor agonist · Phase 3

1–12 mgWeekly doseJastreboff 2023

24.2%Body-weight ↓Jastreboff 2023

~6 daysHalf-life (est)

SQ · Abdomen · Once weekly

01Mechanism of Action

Parameter

BPC-157

Retatrutide

Primary target

VEGFR2 / nitric oxide / FAK-paxillin axes (proposed)Chang 2014 Sikiric 2018

GLP-1R + GIPR + Glucagon receptor (triple agonism)Jastreboff 2023

Pathway

Upregulates VEGFR2 → angiogenesis; modulates NO synthase; promotes fibroblast outgrowth via FAK-paxillinChang 2014

Triple-receptor activation → ↑insulin (GLP-1+GIP), ↓gastric emptying, ↑lipid handling, ↑energy expenditure (glucagon component)Jastreboff 2023

Downstream effect

Accelerated tissue repair, reduced inflammation, improved gut barrier integritySikiric 2018

Maximal weight loss across class. Glucagon component drives lipolysis and energy expenditure beyond GLP-1+GIP aloneJastreboff 2023

Feedback intact?

No known endogenous receptor; mechanism still under investigation

—

Origin

Synthetic pentadecapeptide derived from a sequence in human gastric juice; first characterised by Sikiric et al.Sikiric 2018

Synthetic peptide engineered for balanced affinity at three incretin / glucagon receptorsJastreboff 2023

Antibody development

—

02Dosage Protocols

Parameter

BPC-157

Retatrutide

Standard dose

250–500 mcg / dayHwang 2016

Anecdotal community range. Phase 2 trial used 1.0 mg PL-14736 IV/day.

12 mg / week (max efficacy)Jastreboff 2023

Phase 2 trial dose. Phase 3 dosing TBD.

Frequency

Once or twice daily

Split dosing reported anecdotally for chronic injury.

Once weekly

Lower / starter dose

200 mcg / day

Conservative starter for new users.

—

Evidence basis

Animal-strong + Phase 2 clinicalSikiric 2018 Hwang 2016

Phase 2 trial; Phase 3 ongoingJastreboff 2023

Duration

2–4 weeks (acute injury); 4–8 weeks (chronic)

Anecdotal; no long-term human safety data.

Indefinite for chronic indication (presumed)

Reconstitution

Bacteriostatic water, 1–2 mL

Investigational; not commercially available

Timing

Local SQ to injury site preferred (anecdotal)

Systemic SQ also used; oral bioavailability shown in animal studies.

Any time of day

Half-life

~30 min plasma (estimated)

Tissue half-life longer; mechanism may explain durable effect.

~6 days (estimated from class)

Titration schedule

—

2 mg → 4 mg → 8 mg → 12 mg over 16 weeks

04Side Effects & Safety

Parameter

BPC-157

Retatrutide

Injection site reaction

Mild irritation (anecdotal)

—

GI symptoms

None reported in PL-14736 Phase 2

Nausea, vomiting, diarrhea (very common, dose-dependent)Jastreboff 2023

Cardiovascular

Not reported

—

Cancer risk

Theoretical concern via VEGF angiogenesis pathwaySikiric 2018

—

Antibody formation

No data (no long-term human trials)

—

Pregnancy / OB

Avoid — insufficient safety data

Avoid (insufficient data)

Long-term safety

Unknown beyond Phase 2 trial duration

—

Drug interactions

None established

—

Heart rate

—

↑ resting HR (3–7 bpm at 12 mg)Jastreboff 2023

Glucose handling

—

Glycemic improvement; rare hyperglycemia from glucagon component

Pancreatitis risk

—

Class warning

Thyroid C-cell tumours

—

Class warning (presumed)

Absolute Contraindications

BPC-157

·Pregnancy / breastfeeding
·Known active malignancy (theoretical VEGF concern)

Retatrutide

·MTC personal or family history (presumed class effect)
·Pregnancy / breastfeeding

Relative Contraindications

BPC-157

·History of cancer
·Concurrent VEGF inhibitor therapy (theoretical)
·Acute thrombotic events

Retatrutide

·Severe gastroparesis
·History of pancreatitis
·Severe cardiovascular disease (HR signal)

05Administration Protocol

Parameter

BPC-157

Retatrutide

1. Reconstitution

Add 1–2 mL bacteriostatic water to a 5 mg vial. Roll gently; do not shake. Solution should be clear and colourless.

Investigational peptide. Research vials reconstituted with bacteriostatic water per label.

2. Injection site

Subcutaneous near the injury site is the most common anecdotal route. Systemic SQ (abdomen) also used. Rotate sites.

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

3. Timing

No strict timing requirement. Most users dose once or twice daily, often morning + evening.

Once weekly, same day.

4. Storage

Lyophilised: room temp, light-protected. Reconstituted: refrigerate 2–8 °C, use within 30 days.

Refrigerate 2–8 °C. Light-protected.

5. Needle

27–31G insulin syringe, 4–8 mm. Local injection allows finer 31G.

27–31G, 4–8 mm insulin syringe.

06Stack Synergy

BPC-157

+ TB-500

Strong

View TB-500 →

BPC-157 and TB-500 (Thymosin β-4) target distinct healing axes: BPC-157 upregulates VEGF-driven angiogenesis and fibroblast migration; TB-500 increases actin remodelling and cell migration via the actin-sequestering β-thymosin domain. Stacked, they cover both vascular (BPC) and structural (TB-500) regeneration pathways. Anecdotally favoured for tendon and ligament repair where both pathways contribute.

BPC-157: 250–500 mcg SQ · daily
TB-500: 2 mg SQ · 2× per week
Primary benefit: Tendon/ligament/muscle repair via complementary angiogenesis + migration

Retatrutide

— no documented stacks