Comparison
BPC-157 vs Thymosin Alpha-1
Side-by-side of BPC-157 and Thymosin Alpha-1. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
BPC-157
BPC-157 peptide profile: pentadecapeptide body protection compound 157. Preclinical data on tendon, gut healing, recovery. No human RCTs as of 2026.
Thymosin Alpha-1
Thymosin alpha-1 peptide (Zadaxin, thymalfasin): 28-amino-acid TA1 immunomodulator. Dosing, T-cell effects, hepatitis B and HCV adjunct evidence.
Effects at a glance
BPC-157
- •Preclinical models show accelerated tendon-to-bone and ligament healing after surgical or chemical injury
- •Rodent studies report mucosal protection and faster recovery from NSAID-induced and colitis-induced gut damage
- •Anecdotal human protocols use 250 to 500 mcg twice daily subcutaneously near the injury site
- •No completed phase II or III human RCTs as of 2026, so efficacy and long-term safety remain unestablished
- •Banned by WADA since 2022 under the S0 non-approved substances category for competitive athletes
- •Theoretical angiogenic concern means avoidance is prudent in active malignancy until human data exists
Thymosin Alpha-1
- •28-amino-acid synthetic peptide identical to thymic-derived immunomodulator
- •Approved in over 35 countries as Zadaxin for hepatitis B, hepatitis C adjunct, and immune support
- •Not FDA approved in US; compounded by 503A/503B pharmacies for off-label immune support
- •Modulates T-cell maturation, NK activity, and Th1 polarization in immunocompromised states
- •Standard label dose: 1.6 mg subcutaneously twice weekly
- •Cleanest safety profile in the peptide class with hundreds of regulated trials behind it
Side-by-side
| Attribute | BPC-157 | Thymosin Alpha-1 |
|---|---|---|
| Category | peptide | peptide |
| Also known as | Body Protection Compound-157, Pentadecapeptide BPC-157 | Talpha1, Ta1, Zadaxin, Thymalfasin |
| Half-life (hr) ↗ | 4 | 2 |
| Typical dose (mg) ↗ | 0.25 | 1.6 |
| Dosing frequency | daily (anecdotal protocols) | 2x weekly |
| Routes | subcutaneous, intramuscular, oral | subcutaneous, intramuscular |
| Onset (hr) | - | 24 |
| Peak (hr) | - | 168 |
| Molecular weight | - | 3108.32 |
| Molecular formula | C62H98N16O22 | C129H215N33O55 |
| Mechanism | Proposed upregulation of VEGFR2 and nitric oxide pathways, modulation of growth-hormone receptor expression, and stabilization of gut-brain axis signaling. Mechanism remains largely preclinical. | Synthetic peptide modulator of innate and adaptive immunity. Promotes T-cell maturation and CD4/CD8 production, modulates Th1/Th2 balance, stimulates NK cell activity, and modulates TLR2/TLR9 signaling in dendritic cells. |
| Legal status | Not FDA approved; research-use-only grey market; banned by WADA (2022) | Approved in 35+ countries as Zadaxin (hepatitis B, hepatitis C adjunct, immune support); not FDA approved in US; compounded by 503A/503B pharmacies for off-label use; not on WADA Prohibited List |
| WADA status | banned | unknown |
| DEA / Rx | Not FDA approved; not scheduled; research-chemical status | Rx only via international approval or US compounding (no controlled-substance schedule) |
| Pregnancy | Insufficient data | Not recommended; insufficient data |
| CAS | 137525-51-0 | 62304-98-7 |
| PubChem CID | 9941957 | 16130571 |
| Wikidata | Q4835418 | Q913854 |
Safety profile
BPC-157
Common side effects
- injection-site irritation
- nausea
- headache (anecdotal)
Contraindications
- pregnancy
- active malignancy (theoretical angiogenic concern)
- no established safety profile in humans
Thymosin Alpha-1
Common side effects
- mild injection-site irritation (rare)
- transient mild fatigue (rare)
- occasional headache (rare)
Contraindications
- pregnancy
- lactation
- active organ transplant rejection therapy
- systemic immunosuppression for autoimmune disease (relative)
- severe active autoimmune disease (caution)
Interactions
- interferon-alpha: additive immune effect; used clinically in approved combination protocols(minor)
- calcineurin inhibitors (cyclosporine, tacrolimus): theoretical destabilization of immunosuppression; avoid(major)
- antimetabolites (azathioprine, mycophenolate): theoretical destabilization of immunosuppression; avoid(major)
- vaccine administration: may augment vaccine response in elderly or immunocompromised; coordinate with clinician(minor)
Which Should You Take?
Thymosin Alpha-1 comes out ahead for most readers on the criteria we weight: 3 catalogued goals, Approved in 35+ countries as Zadaxin (hepatitis B, hepatitis C adjunct, immune support); not FDA approved in US; compounded by 503A/503B pharmacies for off-label use; not on WADA Prohibited List, with a Tier-A outcome catalogued. BPC-157 is the right call when one of the conditionals below applies.
- → If your priority is gut barrier and microbiome health, pick BPC-157.
- → If your priority is immune support, pick Thymosin Alpha-1.
- → If your priority is antiviral action, pick Thymosin Alpha-1.
Edge case: If you cannot self-administer injections, BPC-157 is the only oral option in this pair.
Default choice: Thymosin Alpha-1. Wider use case, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for BPC-157 only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between BPC-157 and Thymosin Alpha-1?
BPC-157 and Thymosin Alpha-1 differ in category (peptide vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, BPC-157 or Thymosin Alpha-1?
BPC-157 half-life is 4 hours; Thymosin Alpha-1 half-life is 2 hours.
Can you stack BPC-157 with Thymosin Alpha-1?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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