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Peptide.Guide

FDA Category 2 · restricted from compounding

This compound is on the FDA’s interim Section 503A Category 2 bulks list and cannot be legally compounded by US pharmacies. An HHS announcement in February 2026 signaled intent to restore several peptides to Category 1, but no Federal Register action has been published. Check the FDA PCAC schedule for updates.

Read the full regulatory context
PreclinicalTissue RepairSubQ2–3x per week

TB-500

Thymosin Beta-4 fragment · TB4

Synthetic fragment of thymosin beta-4 promoting actin regulation, cell migration, and tissue repair.

Read dosing protocol

§ 01   Overview

Overview

Synthetic fragment of thymosin beta-4 promoting actin regulation, cell migration, and tissue repair.

Strong preclinical literature; limited human clinical data. WADA-banned for athletes.

§ 02   Mechanism

Mechanism of action

TB-500 sequesters G-actin and regulates actin polymerization, enabling endothelial and stem cell migration to sites of injury. It promotes angiogenesis and downregulates inflammatory mediators.

  • 01Accelerated soft tissue recovery in animal models
  • 02Supports cardiac and vascular repair (preclinical)
  • 03Often stacked with BPC-157 for synergy

§ 03   Dosing

Dosing protocol

Standard Protocol

Vial
5 mg or 10 mg
BAC Water
2 ml BAC water
Dose Range
2 – 5 mg per week (split doses)
Starting Dose
2 mg weekly split EOD
Route
SubQ
Timing
Any time
Frequency
2–3x per week
Cycle
Loading 4–6 weeks, maintenance 2 mg/week

§ 04   Evidence

Evidence & research

Preclinical

Strong preclinical literature; limited human clinical data. WADA-banned for athletes.

FDA Status

Not FDA-approved. WADA prohibited at all times.

§ 05   Stacks

Common stacks

BPC-157

Tissue repair synergy

§ 06   News

In the news

8 articles from the last 12 months · updates hourly

§ 07   Sourcing

Sourcing & supply

Regulatory status

Restricted from compounding

Placed on the FDA's 503A Category 2 list and cannot be lawfully compounded in the US. No brand pharmacy alternative exists. US buyers encounter only research-use-only (RUO) channels, which the FDA's Intended Use Doctrine treats as unapproved drug sales.

503B pharmacies · 1

503B pharmacy

Hallandale Pharmacy (Pharmcore)

Rx required

503A with historic warning letter (2020, closed out 2022). Major telehealth fulfillment partner.

1 flag on record
Visit

Telehealth (Rx) · 1

Telehealth

Defy Medical

Rx required

Broadest peptide formulary in legitimate US telehealth. 13-year history, concierge cash-pay, no known lawsuits.

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International · 5

International

Rupharma

12+ year Russian pharmacy reseller. Reviews.io 4.84/5 (81+). Has a genuine US warehouse for common peptides.

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International

Trident Peptides

1,299+ Trustpilot reviews (5-star). Strongest review base in UK research peptides. No visible ISO/GMP; COAs not posted.

1 flag on record
Visit
International

Direct Peptides

Multi-region geo-routed mirrors. Multiple credible scam complaints. Documented customs seizures. Avoid absent stronger evidence.

2 flags on record
Visit
International

Pharma Lab Global

Budget pricing but significant QC concerns. Claims HPLC+MS 'on request' not displayed.

1 flag on record
Visit
International

Canlab

Health Canada public warning December 2023. Operates across mirror domains to evade takedowns. Avoid.

2 flags on record
Visit

Research-use-only · 7

Research-use-only

Swiss Chems

Established SARMs/peptide vendor. FDA warning letter Dec 2024 for GLP-1s. Weaker peptide QC than SARMs QC.

Third-Party Testing1 flag on record
Visit
Research-use-only

Limitless Life Nootropics

'Only BBB-accredited peptide company' (since 2020). Claims three-lab third-party testing. Broad catalog.

BBB Accredited +1
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Research-use-only

Core Peptides

Broad catalog, widest payment range. Mid-credibility: Knoji 2.5/5 and one scam-impersonation report.

Third-Party Testing1 flag on record
Visit
Research-use-only

Ascension Peptides

Among newer RUO vendors with cleaner credibility signals. SafeCert Labs (CLIA-certified) testing, 4.8 Trustpilot. US-only.

Third-Party Testing
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Research-use-only

Modern Aminos

Multi-vial batch third-party testing. 5-star Trustpilot (1,400+ reviews). US- and EU-facing.

Third-Party Testing
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Research-use-only

Peptide Warehouse

US-made, independent third-party testing including endotoxin and heavy-metal panels. Distinct from similar-sounding copycat domains.

Third-Party Testing1 flag on record
Visit
Research-use-only

BioTech Peptides

Claims >99% purity via HPLC + MS. Accepts cards and PayPal. 30-day money-back.

Third-Party Testing1 flag on record
Visit

Listings are informational, not endorsement. Verify credentials and flags against FDA and PCAB databases before purchasing. Full directory & how to verify →

§ 09   Safety

Safety & side effects

Side effects

  • 01Mild fatigue during loading
  • 02Injection site bruising

Contraindications

None specified.

◆   In this categoryMore from Tissue Repair
01

BPC-157

Pentadecapeptide derived from a gastric protein; widely used in research and compounding for tendon, gut, and soft-tissue repair.

Preclinical
02

GHK-Cu

Copper-binding tripeptide with broad effects on wound healing, collagen synthesis, and hair follicle function.

Clinical
03

KPV

Tripeptide fragment of alpha-MSH with potent anti-inflammatory effects, especially in the gut and skin.

Preclinical
04

BPC-157 (Capsules)

Oral capsule form of BPC-157, targeting gut healing where local action is desirable.

Preclinical
05

BPC-157 + KPV (Capsules)

Combination oral capsule stacking BPC-157 and KPV for gut mucosal healing and anti-inflammatory effects.

Preclinical

This site is for educational and research purposes only. It does not constitute medical advice. Always consult a qualified healthcare provider before using any peptide or supplement.