TB-500 Dosage Calculator

TB-500 is a synthetic peptide fragment corresponding to amino acids 17–23 of thymosin beta-4 (Tβ4), a 43-amino acid protein originally isolated from the thymus gland but now known to be ubiquitously expressed throughout the body, with particularly high concentrations in platelets, wound fluid, and blood cells. The full thymosin beta-4 protein plays a central role in actin dynamics — it sequesters G-actin (globular actin) monomers, regulating the balance between polymerized (F-actin) filaments and free monomers, and thereby controls cell motility, proliferation, and differentiation. The TB-500 fragment (Ac-LKKTETQ) retains much of the parent protein's biological activity and is considerably smaller, contributing to better tissue penetration and distribution.

Research interest in TB-500 is primarily driven by its apparent tissue-healing and regenerative properties demonstrated in animal models. Studies in rodents and horses (where it has been extensively researched in veterinary contexts) have documented accelerated healing of tendon, muscle, ligament, cardiac, and dermal injuries. Several studies suggest TB-500 promotes angiogenesis, reduces inflammation, and decreases myocardial cell death following ischemic injury, making it a compound of interest for both musculoskeletal recovery research and cardiac repair.

TB-500 acts primarily by promoting the polymerization of actin into filaments through sequestration of G-actin monomers, which mobilizes a pool of actin available for cytoskeletal remodeling at sites of injury. This process drives the migration of keratinocytes, endothelial cells, and fibroblasts into wound areas, accelerating tissue repair. The peptide upregulates matrix metalloproteinases and promotes the synthesis of extracellular matrix components including fibronectin and laminin, supporting structural tissue reconstruction.

In cardiac research, TB-500 has been shown to promote endothelial cell survival, reduce cardiomyocyte death after infarction, and stimulate cardiac progenitor cell migration to injury sites. In neurological models, it has demonstrated neuroprotective effects after central nervous system injury, potentially via anti-inflammatory and anti-apoptotic mechanisms. Downregulation of pro-inflammatory cytokines (including IL-6 and TNF-α) has been documented in several in vitro and in vivo studies, consistent with the compound's proposed anti-inflammatory profile.

TB-500 lyophilized powder is reconstituted with bacteriostatic water for injection. For a 5 mg vial, inject 1 mL of bacteriostatic water slowly against the inner wall of the vial. Allow the vial to rest for 60 seconds without disturbance, then gently swirl until the powder dissolves completely. The reconstituted solution should be clear and colorless. For a 10 mg vial, using 2 mL of bacteriostatic water yields the same concentration (5,000 mcg/mL), making dosing calculations consistent.

A 5 mg vial with 1 mL of bacteriostatic water gives 5,000 mcg/mL. A 2.5 mg (2,500 mcg) dose requires 0.50 mL (50 IU on a U100 insulin syringe). Because TB-500 doses are typically in the low milligram range — considerably larger than peptides like ipamorelin or BPC-157 — a larger syringe (1 mL capacity) is generally required. Administer subcutaneously into the abdomen, upper thigh, or upper arm with a 27–29 gauge needle.

Published TB-500 research in animals does not translate perfectly to standardized human-equivalent protocols, but commonly referenced research community dose ranges are based on veterinary and preclinical data. A frequently cited loading protocol involves administering 5–7.5 mg per week divided into two to three doses per week for the first four to six weeks, followed by a maintenance phase of 2.5 mg once or twice per week.

In equine veterinary research, TB-500 doses of 5–10 mg per injection (systemically) have been used for musculoskeletal injuries. In rodent studies, subcutaneous doses of 1.5–3 mg/kg have produced significant angiogenic and repair effects. For a 70 kg human-equivalent, body surface area scaling from rat data suggests doses in the 1.5–3 mg range, consistent with commonly discussed protocols.

Some research protocols combine TB-500 with BPC-157 in a paired approach, given their complementary mechanisms. Typical cycle lengths in research contexts run four to eight weeks, with rest periods between cycles. Using the calculator: a 5 mg vial with 1 mL gives 5,000 mcg/mL. A 2.5 mg dose requires exactly 0.50 mL (50 IU). A 5 mg dose requires the full 1 mL of reconstituted solution.

Lyophilized TB-500 powder is stable at room temperature for short periods but should be stored at 2–8°C for research use and at -20°C for long-term archival storage. Avoid repeated freeze-thaw cycles of the dry powder. Once reconstituted in bacteriostatic water, store at 2–8°C and use within 28 days. TB-500 is generally considered a reasonably stable peptide in solution at refrigerator temperatures due to its small size (seven amino acids) and stable linear structure. Protect from direct light; use amber vials if available for long-term storage of the reconstituted solution.

TB-500 has demonstrated low toxicity in preclinical rodent studies at research doses. No dose-limiting toxicities have been identified in animal models at therapeutically relevant dose ranges, and no published evidence of organ toxicity has emerged from the available animal literature. The peptide has been used extensively in veterinary practice for equine tendon and muscle injuries with a reported favorable safety profile. Formal human clinical trial data is lacking; a small number of Phase 1/2 trials using full-length thymosin beta-4 have been conducted for cardiac and ophthalmic indications, showing tolerability in early-phase studies. TB-500 remains a research chemical for laboratory investigation only, without established human safety or efficacy data.