Side-by-side · Research reference
BPC-157vsSS-31
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 3Reviewed9/43 cited
BPC-157
Stable Gastric Pentadecapeptide · Healing
SQ or IM · Local · Once or twice daily
SS-31
Cardiolipin-binding · Mitochondrial protective
SQ · Abdomen · Once daily
01Mechanism of Action
Parameter
BPC-157
SS-31
Primary target
VEGFR2 / nitric oxide / FAK-paxillin axes (proposed)Chang 2014Sikiric 2018
Cardiolipin in inner mitochondrial membraneSzeto 2014
Pathway
Upregulates VEGFR2 → angiogenesis; modulates NO synthase; promotes fibroblast outgrowth via FAK-paxillinChang 2014
Cardiolipin binding → cristae stabilisation → ETC integrity → reduced ROS + preserved ATP synthesisSzeto 2014Szilagyi 2009
Downstream effect
Accelerated tissue repair, reduced inflammation, improved gut barrier integritySikiric 2018
Mitochondrial bioenergetic preservation; cardio-, neuro-, and reno-protective effects in animal + clinical studiesSzeto 2014
Feedback intact?
No known endogenous receptor; mechanism still under investigation
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Origin
Synthetic pentadecapeptide derived from a sequence in human gastric juice; first characterised by Sikiric et al.Sikiric 2018
Synthetic tetrapeptide D-Arg-Dmt-Lys-Phe-NH₂; cell-permeable, mitochondrial-selectiveSzeto 2014
Antibody development
—
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02Dosage Protocols
Parameter
BPC-157
SS-31
Standard dose
250–500 mcg / dayHwang 2016
Anecdotal community range. Phase 2 trial used 1.0 mg PL-14736 IV/day.
40 mg / day SQ (clinical trials)Szeto 2014
Anecdotal community range 5-10 mg/day. Phase 3 trials use 40 mg.
Frequency
Once or twice daily
Split dosing reported anecdotally for chronic injury.
Once daily
Lower / starter dose
200 mcg / day
Conservative starter for new users.
5 mg / day (anecdotal)
Evidence basis
Animal-strong + Phase 2 clinicalSikiric 2018Hwang 2016
Multiple Phase 3 trials (Barth, AMD, ischemia-reperfusion)Szeto 2014Szilagyi 2009
Duration
2–4 weeks (acute injury); 4–8 weeks (chronic)
Anecdotal; no long-term human safety data.
Indefinite for mitochondrial disease; cycled for healthspan use
Reconstitution
Bacteriostatic water, 1–2 mL
Bacteriostatic water
Timing
Local SQ to injury site preferred (anecdotal)
Systemic SQ also used; oral bioavailability shown in animal studies.
Morning fasted preferred; pre-workout for exercise-induced mitochondrial stress
Half-life
~30 min plasma (estimated)
Tissue half-life longer; mechanism may explain durable effect.
~3 h plasma; tissue uptake longer
04Side Effects & Safety
Parameter
BPC-157
SS-31
Injection site reaction
Mild irritation (anecdotal)
Erythema, mild pruritus
GI symptoms
None reported in PL-14736 Phase 2
Nausea (uncommon)
Cardiovascular
Not reported
Cardio-protective in studies; no signal of harm
Antibody formation
No data (no long-term human trials)
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Pregnancy / OB
Avoid — insufficient safety data
Avoid — insufficient data
Long-term safety
Unknown beyond Phase 2 trial duration
Phase 3 data over 24+ months; no major safety signalsSzeto 2014
Drug interactions
None established
—
Headache
—
Reported in some Phase 3 trials
Absolute Contraindications
BPC-157
- ·Pregnancy / breastfeeding
- ·Known active malignancy (theoretical VEGF concern)
SS-31
- ·Pregnancy / breastfeeding
- ·Hypersensitivity to peptide
Relative Contraindications
BPC-157
- ·History of cancer
- ·Concurrent VEGF inhibitor therapy (theoretical)
- ·Acute thrombotic events
SS-31
- ·None established
05Administration Protocol
Parameter
BPC-157
SS-31
1. Reconstitution
Add 1–2 mL bacteriostatic water to a 5 mg vial. Roll gently; do not shake. Solution should be clear and colourless.
Add bacteriostatic water per label. Light-protected handling.
2. Injection site
Subcutaneous near the injury site is the most common anecdotal route. Systemic SQ (abdomen) also used. Rotate sites.
SQ — abdomen or thigh. Rotate sites.
3. Timing
No strict timing requirement. Most users dose once or twice daily, often morning + evening.
Morning fasted; pre-workout for exercise-augmented mitochondrial stress.
4. Storage
Lyophilised: room temp, light-protected. Reconstituted: refrigerate 2–8 °C, use within 30 days.
Lyophilised: refrigerate, light-protected. Reconstituted: refrigerate ≤30 days.
5. Needle
27–31G insulin syringe, 4–8 mm. Local injection allows finer 31G.
29–31G, 4–8 mm insulin syringe.
06Stack Synergy
BPC-157
+ TB-500
StrongBPC-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
SS-31
+ MOTS-c
ModerateSS-31 and MOTS-c address mitochondrial decline through complementary axes. SS-31 protects existing mitochondrial structure (cardiolipin binding, cristae stabilisation). MOTS-c upregulates AMPK/PGC-1α, triggering biogenesis of new mitochondria. Together they pair preservation with renewal — anecdotally favoured in healthspan and post-cardio-event recovery protocols.
- SS-31
- 5–10 mg SQ · daily morning
- MOTS-c
- 5 mg SQ · 2× per week pre-workout
- Primary benefit
- Mitochondrial preservation + biogenesis