Peptide profile · Healing & Recovery
TB-500
A powerful fragment of thymosin beta-4 that acts like your body's repair signal—speeding up healing of muscles, tendons, and tissues by promoting cell migration and new blood vessel growth right where you need it most.
Written & reviewed by Michael Carroll · Research, Peptide Initiative
Typical dose
2-2.5 mg
Half-life
2-3 days (systemic)
Bioavailability
High via subcutaneous injection (~100%)
Molecular weight
889.01 g/mol
Evidence level
Moderate human trials
01 · Compound profile
Scientific & efficacy data
Molecular formula
C38H68N10O14
Primary benefits
Accelerates tissue repair through cell migration and angiogenesis—one of the most effective peptides for injury recovery
Regenerates muscle, tendon, and ligament tissue by promoting new blood vessel formation and reducing inflammation
Prevents fibroblast-to-myofibroblast conversion, reducing scar tissue formation and preserving tissue flexibility
George Washington University School of Medicine
Amino acid sequence
Ac-LKKTETQ (N-Acetyl-Leu-Lys-Lys-Thr-Glu-Thr-Gln)02 · Dosing
How much do I take?
2-2.5 mg · once weekly
Subcutaneous: A small injection into the fatty layer just under the skin — the same way insulin is given.
Bioavailability High — most of the dose reaches your bloodstream, just more gradually than an IV.
Best time to take
Morning or evening—timing doesn't significantly affect TB-500's effectiveness. What matters most is consistency. Pick a schedule that works for your lifestyle and stick with it.
With food?
TB-500 can be injected regardless of food timing. It doesn't seem to affect absorption either way, so fit it into whatever routine works for you.
If stacking
TB-500 pairs exceptionally well with BPC-157—they're often called the 'healing stack' because they work through different but complementary mechanisms. Inject at different sites if using both. Space injections at least 15-30 minutes apart to track individual effects.
＋ Increase if
- +You've completed 2+ weeks at starting dose with minimal healing progress
- +Your injury is more severe than initially assessed
- +You're recovering from surgery under professional guidance
- +Your research protocol calls for loading phases
－ Decrease if
- −You experience persistent headaches or fatigue beyond the first week
- −Injection site reactions don't resolve within 48 hours
- −You feel unusually tired or lethargic after each injection
- −Any unexpected or uncomfortable side effects arise
✓ Signs of right dose
- ✓Noticeable improvement in injury flexibility or reduced stiffness
- ✓Decreased pain at the injury site over 2-4 weeks
- ✓Improved range of motion in affected areas
- ✓Better exercise tolerance without aggravating the injury
Dosing Calculator
Calculate Your Exact Dose
Step 1: Peptide Weight
Find the weight printed on your peptide vial label
Look here!
The peptide weight is printed on the label
Look here!
The weight is on the label
Select Weight
Look for a number followed by 'mg' on the vial label (e.g., 5mg, 10mg)
03 · Suitability
Is this right for me?
Best for accelerating injury recovery & tendon and ligament healing
Best for
Athletes Recovering from Muscle Injuries
If you've pulled a hamstring, strained your back, or torn a muscle, TB-500 helps accelerate the healing process by promoting cell migration to the injury site and supporting new blood vessel growth. It's especially useful for injuries that just won't seem to fully heal.
Tendon and Ligament Problems
Tendons and ligaments are notoriously slow healers because they have poor blood supply. TB-500 promotes angiogenesis (new blood vessel formation) and helps repair these stubborn connective tissue injuries—think Achilles tendonitis, tennis elbow, or rotator cuff issues.
Post-Surgical Recovery
After surgery, your body needs to repair a lot of tissue quickly. TB-500 supports wound healing, reduces inflammation, and may help minimize scar tissue formation. Some protocols use it alongside traditional recovery to potentially speed up the healing timeline.
Chronic Inflammation and Slow Healers
Some people just heal slowly—whether due to age, diabetes, or other factors. TB-500 helps regulate the inflammatory response and promotes the cellular processes needed for tissue repair. It essentially tells your body to focus healing resources where they're needed most.
Consider alternatives if
Do not use if
Use with caution if
Not sure?
Compare TB-500 with similar peptides to find the best fit for your goals.
04 · Administration
How do I use it?
Subcutaneous injection · Intramuscular injection
Reconstitution — what you need
Example
If you have a 5mg vial and add 2mL of BAC water, you get a concentration of 2.5mg/mL. So every 1mL (100 units on an insulin syringe) equals 2.5mg of TB-500.
For a 2.5mg dose at 2.5mg/mL concentration: draw 1mL (100 units on a standard insulin syringe). For a 5mg dose: draw the full 2mL or use a larger vial reconstituted accordingly.
Route
Subcutaneous injection (just under the skin)—the easiest and most common method. Some users prefer injecting near the injury site, though systemic administration works well too.
Best sites
Technique
- 01Wash your hands thoroughly with soap and water
- 02Clean the injection site with an alcohol swab and let it air dry completely
- 03Pinch about an inch of skin to create a fold
- 04Insert the needle at a 45-90 degree angle (45 if you're lean, 90 if you have more tissue)
- 05Push the plunger slowly and steadily
- 06Wait 5 seconds before removing the needle
- 07Apply light pressure if needed—don't rub
Storage · before reconstitution
Keep your TB-500 powder in the refrigerator (36-46°F / 2-8°C) for short-term storage or in the freezer (-4°F / -20°C) for long-term storage. Store in the original sealed vial away from light. Properly stored powder can remain stable for 2+ years when frozen.
Storage · after reconstitution
Once mixed with bacteriostatic water, refrigerate at 36-46°F (2-8°C). Never freeze the reconstituted solution—freezing destroys the peptide. Keep away from light and use within 28 days.
Signs of degradation
Sample daily schedule
05 · Safety
Is it safe?
4 common side effects · 1 serious
TB-500 has shown a good safety profile across preclinical studies and limited human research. It's a fragment of thymosin beta-4, a naturally occurring protein in your body involved in healing. Most side effects are mild and transient, primarily injection site reactions. However, large-scale clinical trials are still needed to fully establish its safety profile in humans.
TB-500 has been used extensively in equine medicine and has been the subject of multiple human clinical trials for conditions like dry eye, wound healing, and cardiac repair. Phase 1-2 trials have shown it to be well-tolerated, but Phase 3 data is limited. Always work with a healthcare provider when using research compounds.
Common side effects · experienced by some users
Less common
These typically resolve with continued use or dose adjustment.
Stop and seek help if
- ×Any signs of allergic reaction—stop immediately and seek medical help
- ×Persistent headaches or fatigue that don't improve after the first week
- ×Significant injection site reactions that spread or don't heal
- ×Any side effect that feels serious or really concerns you
- ×Your injury has healed satisfactorily
- ×Your research protocol/cycle is complete
TB-500 is a research compound, not an FDA-approved medication. Never start, stop, or change your dosing without guidance from a qualified healthcare provider. This information is for educational purposes only—not medical advice.
With other peptides
- ✓BPC-157 — Excellent pairing—the classic 'healing stack.' BPC-157 works through different pathways and together they provide comprehensive tissue repair support. Inject at different sites.
- ✓GHK-Cu — Safe to combine for comprehensive tissue repair. GHK-Cu focuses on skin and collagen while TB-500 works on deeper tissue healing.
- ✓IGF-1 LR3 — Can be combined for enhanced muscle recovery. Both promote tissue repair through different mechanisms.
- ✓CJC-1295/Ipamorelin — Safe to stack for overall recovery. Growth hormone releasing peptides complement TB-500's healing effects.
With medications
- !Blood thinners (warfarin, heparin) — May increase bleeding at injection sites. TB-500 promotes angiogenesis which could theoretically affect clotting. Monitor closely.
- ✓NSAIDs (ibuprofen, naproxen) — NSAIDs reduce inflammation which is part of the healing process TB-500 supports. May reduce effectiveness—use sparingly.
- ✓Corticosteroids — Steroids can impair healing. If you're on long-term steroids, discuss with your doctor.
- ✓Diabetes medications — TB-500 supports wound healing in diabetics but monitor blood sugar as healing processes can affect glucose.
With supplements
- ✓Collagen peptides — Complementary—collagen provides building blocks while TB-500 promotes the repair process.
- ✓Omega-3 fatty acids — Safe and potentially beneficial. Omega-3s support anti-inflammatory pathways that complement healing.
- ✓Vitamin C — Supports collagen synthesis and healing. Good addition to a recovery protocol.
- ✓Turmeric/Curcumin — Anti-inflammatory but work differently than NSAIDs. Generally considered safe to combine.
06 · Effectiveness
How do I know it's working?
Moderate human trials · first signs week 1
Evidence level
Moderate human trials
(Phase 1-2)
How it works
Think of TB-500 as your body's 'come here and help' signal for healing. When you get injured, your body naturally releases thymosin beta-4 to start the repair process. TB-500 is a synthetic version of the most active part of this protein. It works by telling your cells to migrate to the injury site, promoting the growth of new blood vessels to bring oxygen and nutrients, and reducing inflammation so healing can happen properly. It also helps prevent excessive scar tissue formation, so you heal with more functional tissue instead of stiff scar tissue. It's like giving your body's repair crew a megaphone and extra supplies.
TB-500 (Ac-LKKTETQ) is a synthetic heptapeptide corresponding to the active region (17-23) of thymosin beta-4 (Tβ4). Its primary mechanism involves sequestration of G-actin monomers, regulating actin polymerization and enabling cytoskeletal reorganization necessary for cell migration. TB-500 upregulates actin expression and promotes the formation of extracellular matrix proteins through activation of cell surface receptors. The peptide stimulates angiogenesis through the VEGF/Akt/eNOS pathway, promoting endothelial progenitor cell differentiation and blood vessel formation. It exhibits anti-inflammatory properties by reducing macrophage infiltration and downregulating pro-inflammatory cytokines including TGF-β and IL-10. TB-500's anti-fibrotic effects occur through inhibition of fibroblast-to-myofibroblast differentiation, mediated partly by its N-terminal sequence Ac-SDKP. The peptide also demonstrates neuroprotective properties by reducing apoptosis, promoting oligodendrogenesis, and supporting neural stem cell differentiation. These multi-pathway effects make it a comprehensive tissue repair and regeneration agent.
What to expect
Week 1
What you might notice
- •Mild injection site redness (totally normal)
- •Possibly some initial fatigue or mild headache
- •Slight reduction in inflammation at injury site
- •Your body is just getting introduced to the peptide
What's normal
- •Minor injection site reactions that fade within a day
- •Feeling a bit tired on injection days
- •No dramatic changes yet—healing takes time
What's next
- →Keep following your protocol consistently
- →Track any changes in your injury or range of motion
- →Side effects typically improve after the first week
Weeks 2-3
What you might notice
- •Reduced stiffness around the injury
- •Improved flexibility or range of motion
- •Decreased pain with movement
- •Less swelling if inflammation was present
What's normal
- •Gradual improvement rather than sudden changes
- •Good days and less-good days are normal
- •Injury still present but progressing
What's next
- →Continue your protocol through the full cycle
- →Begin gentle movement or rehab exercises if appropriate
- →Don't push the injury too hard yet
Weeks 4-6
What you might notice
- •Significant improvement in injury healing
- •Better function of the affected area
- •Reduced or resolved pain
- •Ability to return to normal activities gradually
What's normal
- •Major improvement for most users by week 4-6
- •Some stubborn injuries may need extended protocols
- •Complete healing of muscle injuries, continued progress on tendons
What's next
- →Complete your cycle and assess results
- →Transition to maintenance dose if needed
- →Resume full activity cautiously with proper rehabilitation
Signs it's working · Injury Recovery Indicators
- ✓Reduced pain at the injury site
- ✓Improved range of motion in affected joints
- ✓Decreased stiffness, especially in the morning
- ✓Less swelling and inflammation
- ✓Better function during daily activities
Signs it's working · Healing Progress
- ✓Wounds closing more quickly than expected
- ✓Reduced bruising duration
- ✓Faster return to physical activities
- ✓Less need for pain medication
- ✓Improved tissue flexibility
Signs it's working · Physical Performance
- ✓Ability to exercise without aggravating injury
- ✓Improved strength in previously injured area
- ✓Better recovery between workouts
- ✓Reduced compensation patterns from injury
Not seeing results? Common reasons
- •Not giving it enough time—TB-500 works over weeks, not days. Tendons especially take 4-8 weeks to show major improvement
- •Dose too low for the injury severity—stubborn injuries may need higher loading doses initially
- •Poor quality peptide from unreliable source—always get third-party testing certificates (COAs)
- •Improper storage degraded the peptide—check if your solution looks clear before using
- •Still aggravating the injury with activity—healing peptides work best when you give the injury rest
- •NSAIDs blocking the healing process—these anti-inflammatory drugs can interfere with tissue repair signals
Key research
07 · Questions
Frequently asked
What's the difference between TB-500 and thymosin beta-4?+
Thymosin beta-4 is the full 43-amino-acid protein naturally produced in your body. TB-500 is a synthetic 7-amino-acid fragment (the 'active region') that contains most of the healing benefits. Think of it like using the key part of a larger molecule. TB-500 is easier to synthesize and more stable, which is why it's commonly used in research.
Can I inject TB-500 directly into my injury?+
You can inject near the injury site (within a few inches), and some users believe this provides localized benefits. However, TB-500 works systemically—it spreads throughout your body via your bloodstream. Subcutaneous belly injections work just as well because the peptide naturally migrates to where it's needed. Don't inject directly INTO injured tissue.
How long until I notice healing improvements?+
Most users notice reduced inflammation and improved flexibility within 1-2 weeks. Significant healing improvements typically appear by weeks 3-4 for muscle injuries. Tendon and ligament injuries take longer—expect 4-8 weeks for noticeable progress. The more severe the injury, the longer it takes.
Should I combine TB-500 with BPC-157?+
This combination is very popular and often called 'the healing stack.' They work through different mechanisms: TB-500 promotes cell migration and blood vessel formation, while BPC-157 works more locally and affects growth factors differently. Together they provide comprehensive tissue repair support. Inject at different sites.
Will TB-500 help an old injury that never fully healed?+
Possibly, yes. TB-500 can help restart the healing process in chronic injuries by promoting cell migration, new blood vessel formation, and tissue remodeling. However, very old injuries with significant scar tissue may have limited improvement. It's worth trying, especially combined with physical therapy.
Is TB-500 banned in sports?+
Yes, TB-500 (and thymosin beta-4) are prohibited by WADA (World Anti-Doping Agency) and most sports organizations under the category of peptide hormones and growth factors. Athletes subject to drug testing should not use TB-500.
Can I use TB-500 for general recovery, not just injuries?+
Some users report improved overall recovery from exercise and general well-being. However, TB-500 is primarily studied for injury healing. If you're looking for general recovery support without an injury, other peptides like BPC-157 or growth hormone secretagogues might be more appropriate.
How does TB-500 reduce scarring?+
TB-500 prevents fibroblasts from transforming into myofibroblasts—the cells that produce excessive scar tissue. It also reduces TGF-beta, a major driver of fibrosis. The result is that injured tissue heals with more normal, functional tissue rather than stiff scar tissue.
What is TB-500?+
TB-500 is a synthetic fragment of thymosin beta-4, a naturally occurring healing protein found in nearly all human and animal cells. The fragment reproduces the parent protein's active region, which promotes cell migration, blood-vessel formation, and reduced inflammation at injury sites. In research settings it's studied for muscle, tendon, and ligament recovery — it acts systemically, traveling through the body rather than working only where injected. See the full profile below for mechanism and studies, or the TB-500 vs thymosin beta-4 comparison for how the fragment differs from the full protein.
What is the typical TB-500 dosage?+
Research protocols typically run in two phases: a loading phase of 2–2.5mg injected subcutaneously twice weekly (commonly 4–6 weeks), then a maintenance phase of 2–2.5mg once weekly. Athletes and bodybuilders researching recovery generally follow the same structure — the loading phase during active injury recovery, maintenance after. TB-500's long half-life is why dosing is weekly rather than daily. See the dosing protocol page for schedules, timing, and adjustment guidance.
What are the side effects of TB-500?+
Reported side effects in research use are generally mild: injection-site redness, temporary fatigue or lethargy, mild headache, and slight flushing are the most common. Less commonly, a brief head rush or lightheadedness and temporary nausea have been reported shortly after injection. As with any peptide, allergic reaction is possible and is the one serious reaction to watch for — discontinue and seek medical care for signs like difficulty breathing or significant swelling. The safety section below covers management for each.
08 · Further reading
History & related research
History · since 1966
The Body's Master Healer — From Horse Racing Scandal to Medical Marvel
Discovered in a gland the size of a walnut, this 43-amino-acid peptide tells your body how to repair itself. Its journey from calf thymus to banned substance to promising medicine is one of science's most dramatic tales.
Read the full history of TB-500