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Thymosin Beta-4

peptide

TB4 · parent of TB-500

Recovery-focused research peptide

Research status · Not FDA-approved

Not FDA-approved for human use; a research peptide. TB-500 is a synthetic fragment often marketed under this name. No completed human randomized trials; prohibited in sport (WADA).

Thymosin Beta-4 is a naturally occurring peptide discussed in tissue-repair contexts and closely related to the marketed TB-500 fragment. It is not approved for human use and human data are sparse — clinician guidance is essential.

How it works

Involved in actin regulation, cell migration, and tissue-repair signaling (largely preclinical).

Commonly discussed use cases

  • Soft-tissue recovery (discussed)
  • Range of motion (discussed)

Supposed / potential benefits

  • Repair claims are largely preclinical/anecdotal, not established in humans

Common side effects

  • Injection-site reactions
  • Headache/lethargy (reported)
  • Unknown long-term effects

Warnings & contraindications

  • Not FDA-approved; flagged for compounding safety concerns
  • Banned in sport (WADA)
  • Unregulated sourcing risk

Typical timing considerations

No established regimen; any use should be clinician-directed. Exhaust conventional rehab first.

Administration route

Subcutaneous or intramuscular injection

Storage

Refrigerate after reconstitution; follow instructions.

Questions to ask your clinician

  • Should conventional rehab come first?
  • What are the risks given limited human evidence?

Commonly tracked in Reta

Target symptom rating (daily)Rehab doneInjection site rotationNew symptoms

Tracking fields organize user-entered, clinician-directed routines — Reta never recommends or computes doses.

Sources

Track this in Reta

Beta members get a ready-made tracker for Thymosin Beta-4 — schedule, dose log, injection-site rotation, reminders, and check-ins — for organizing a clinician-directed routine. Personal tracking is available to everyone during the Public Beta.

Reta is a tracking and education tool — not a medical provider. Nothing here is a diagnosis, treatment, prescription, or dosing recommendation. Peptides and medications should only be used under the direction of a licensed clinician. Talk to a qualified clinician before starting, stopping, combining, or changing anything. Many compounds below are not FDA-approved for human use; some are investigational or sold through unregulated channels where purity and dosing are not guaranteed.