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TB-500 calculators

Reconstitution, dose, mg ↔ units, and vial duration — all four TB-500 calculators in one place, pre-filled with a 5 mg / 2 mL example.

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TB-500 is a synthetic fragment of the natural protein Thymosin Beta-4 that people use to support recovery from soft-tissue and tendon injuries. It works by promoting cell migration and new blood-vessel formation at injury sites, which is what allows damaged tissue to rebuild faster. Animal studies show meaningful acceleration of wound and tendon healing; controlled human data is limited. This page covers reconstitution math and how people typically log a loading-then-maintenance schedule.

How the four TB-500 calculators connect

This tool turns the three numbers on your TB-500 vial into the only number that matters at injection time: how many units to draw on a U-100 insulin syringe. The math is one formula — concentration in mg per mL equals the milligrams of peptide in the vial divided by the milliliters of bacteriostatic water you add — and every other answer falls out of that.

In the worked example below, a 5 mg vial of TB-500 reconstituted with 2 mL of BAC water produces a concentration of 2.5 mg/mL. To draw the example dose of 2 mg from that vial you pull 0.80 mL — about 80 units on a standard insulin syringe. Change any input and the rest updates instantly so you can pre-plan a vial before you ever touch a needle.

Vial size, diluent volume, and dose are the three inputs that genuinely change the answer. Doses-per-vial is a derived output — it's the vial mg divided by the dose mg, rounded down. The most common edge case is a tiny dose: at very high concentration, a 0.1 mL draw is only a few units on the syringe, which is hard to read accurately. If your unit count drops below five, consider reconstituting the next vial with more BAC water so each dose covers a larger volume.

Use this calculator any time you open a fresh vial, switch BAC water volume, or step a titration dose up. Each new vial gets its own concentration and its own unit count — the previous vial's numbers do not carry over, and that is the single most common reconstitution mistake.

What the TB-500 calculators cover

TB-500 is a synthetic peptide fragment corresponding to the active region of Thymosin Beta-4, an exceptionally abundant protein found within the cytoplasm and nucleus of most human and animal cells. Specifically, it often represents the LKKTETQ amino acid sequence, which is believed to be central to the parent protein's primary biological function of sequestering actin monomers. Thymosin Beta-4 is widely distributed throughout the body and is upregulated during embryonic development and in response to injury. Consequently, its synthetic fragment, TB-500, has become a subject of focused scientific inquiry in contexts related to tissue repair, cellular regeneration, and inflammatory modulation, where research models often explore how this specific fragment can replicate the functional effects of the much larger, naturally-occurring 43-amino-acid protein.

The molecular characteristics of TB-500 distinguish it from many smaller peptides, notably in its larger size and an effective dose range measured in milligrams (mg) instead of micrograms (mcg). This larger magnitude has direct consequences for laboratory procedures, influencing how solutions are reconstituted, what diluent volumes are practical, and how doses are measured for administration. In personal-tracking logs, this peptide is most frequently documented with a weekly or twice-weekly cadence, sometimes following an initial 'loading' period of more frequent administration designed to reach a steady-state concentration more rapidly. It is also commonly logged alongside BPC-157, a combination where the two compounds' distinct mechanisms and cadences are viewed as complementary rather than competitive.

How TB-500 is studied

The proposed mechanism of TB-500 is directly inherited from its parent protein, Thymosin Beta-4, which functions as the primary G-actin-sequestering molecule inside cells. G-actin (globular actin) monomers are the fundamental building blocks of F-actin (filamentous actin), which forms the microfilaments of the dynamic cellular cytoskeleton. By binding to G-actin with a 1:1 stoichiometry, Thymosin Beta-4 controls the available pool of monomers and thus modulates the rate and spatial dynamics of actin polymerization. This intricate process of cytoskeletal rearrangement is fundamental to a cell's ability to change shape, exert force, move, and divide, making it a critical control point for cell motility and migration.

This specific actin-modulating activity is the molecular basis for the effects observed in research studies examining wound closure, inflammation, and tissue protection. For a cell to migrate—such as a keratinocyte moving into a wound bed, a fibroblast depositing extracellular matrix, or an endothelial cell forming a new blood vessel—it must be able to rapidly assemble and disassemble its actin cytoskeleton to crawl and navigate its environment. By influencing this core cellular machinery, TB-500 is studied for its potential to support these actin-dependent processes. This mechanism is biochemically distinct from pathways targeted by other peptides, such as those that directly stimulate angiogenic growth factors or activate specific G-protein coupled receptors, explaining its unique profile in research.

How people log TB-500

Logs documenting TB-500 administration most often show a subcutaneous cadence of once or twice per week, a pattern consistent with a molecule expected to have a prolonged duration of action. Some experimental designs incorporate an initial loading phase, where administration might occur several times per week for one to four weeks, before transitioning to a less frequent maintenance schedule. Due to the milligram-scale doses, a 1mL or 0.5mL U-100 insulin syringe is typically used to accurately draw the calculated volume from the reconstituted vial. Rotation of injection sites is a standard practice recorded in detailed logs to monitor for any localized skin reactions.

When planned in conjunction with a peptide requiring daily administration, like BPC-157, TB-500 is scheduled on its own rhythm within the week. A tracker might record daily BPC-157 entries while logging TB-500 doses only on Mondays and Thursdays, for example. This separation ensures that each protocol can be monitored independently without complex timing interactions. The precise time of day for a TB-500 dose is often considered less critical than for short-acting peptides, as the goal is to maintain a stable systemic concentration over many days rather than targeting a narrow post-injection activity window.

Common TB-500 mistakes to avoid

  • Assuming the same unit measurement as BPC-157 when they are stacked, leading to a significant under-dose of TB-500 due to its milligram-scale dosing.
  • Entering a 2.5 mg dose into a calculator field that defaults to micrograms (mcg), resulting in a miscalculation of several orders of magnitude.
  • Allowing a twice-weekly schedule to drift by a day each week, altering the dosing interval from a 3-day/4-day pattern to a 4-day/5-day pattern over time.
  • Using only 1 mL of diluent for a 10 mg vial and finding the resulting solution too concentrated to measure small dose adjustments precisely on a U-100 syringe.
  • Failing to log the 'loading' phase parameters separately from the 'maintenance' phase, making it difficult to analyze the distinct periods of the protocol later.

Frequently asked questions about TB-500

Why are TB-500 doses measured in milligrams (mg) while many others are in micrograms (mcg)?
The dosage scale is related to the peptide's molecular structure and the concentrations studied in research literature. TB-500 is a fragment of a larger, naturally abundant protein, and the quantities examined for biological activity are correspondingly higher than those for smaller synthetic peptides that act on highly sensitive receptors. This difference in magnitude necessitates using milligrams as the unit of measurement for accurate planning, calculation, and tracking.
If I use a 5 mg vial and 2 mL of diluent, how many units do I draw for a 2 mg dose?
With a 5 mg vial reconstituted with 2 mL of bacteriostatic water, the concentration becomes 2.5 mg per mL. To calculate a 2 mg dose, you would need 0.8 mL of the solution. On a U-100 insulin syringe, where 100 units equal 1 mL, 0.8 mL is equal to 80 units. Using a dose calculator is the most reliable way to convert your desired milligram dose into the correct syringe units.
What is the rationale behind a twice-weekly administration schedule?
The less frequent administration schedule, such as twice per week, documented in research logs for TB-500 is generally associated with a longer biological half-life compared to peptides requiring daily or more frequent dosing. This allows for sustained systemic levels to be maintained without the logistic complexity of daily administration. The specific interval (e.g., Monday/Thursday) is chosen to keep peptide concentrations relatively consistent throughout the week.
How does TB-500's mechanism differ from that proposed for BPC-157?
Research suggests they operate through different primary pathways. TB-500's proposed mechanism involves modulating actin dynamics, a fundamental intracellular process for cell structure and migration. In contrast, BPC-157 is primarily studied for its influence on the nitric oxide (NO) system and its effects on angiogenesis (the formation of new blood vessels), largely extracellular and signaling-based activities. Because these mechanisms are distinct, they are often studied in combination to observe their potentially complementary roles.
Is a 'loading phase' documented in research protocols?
Some logs and research reports document a 'loading phase,' characterized by more frequent or higher doses for an initial period, followed by a lower-dose 'maintenance phase.' The theory is to more rapidly elevate systemic concentrations to a steady state. However, other protocols begin directly with a maintenance-style cadence. Tracking logs show both approaches being used, and the decision to use a loading phase is a key variable to document when planning and reviewing a research cycle.
Can I pre-load syringes with TB-500 for a week?
Pre-loading syringes introduces additional stability variables, primarily concerning the interaction of the reconstituted peptide with the syringe materials over time. The stability of most peptides is best characterized in sterile glass vials, not in plastic syringes where factors like surface adsorption and interaction with the rubber plunger are unknown. For this reason, the standard practice documented is to draw each dose from the refrigerated vial immediately before administration to ensure consistency and minimize potential degradation.

Related on Peptide Pilot

Track TB-500 doses in the app

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