Last March, a guy named Derek in Scottsdale called our clinical support line six minutes after his first reconstitution attempt. "I pulled 80 units and the syringe is basically full," he said. "That can't be right." It was right. He'd mixed his 5 mg vial with 2 mL of bacteriostatic water, wanted 2 mg, and 80 units on a U-100 insulin syringe is exactly what that math spits out. The volume looks alarming if you're used to small-volume injections, but the math was clean. Derek's confusion is the single most common question our pharmacy team fields about TB-500 dosage.
So let's walk through the numbers, the protocols, and the practical details that matter when you're actually standing at your kitchen counter with an alcohol swab and a syringe.
Quick framing: the standard compounded TB-500 protocol uses a loading phase of 2 to 2.5 mg subcutaneously twice weekly for four to six weeks, then drops to 2 mg once weekly for maintenance. Your prescriber sets the specifics after evaluating you individually. Everything below reflects how the peptide is discussed in published research and clinical case reports, not an FDA-approved label (because one doesn't exist).
The Peptide in Your Vial
TB-500 is a synthetic analog of a segment of the thymosin beta-4 (Tβ4) protein. Compounding pharmacies typically supply it as a lyophilized white powder in 2 mg, 5 mg, or 10 mg vials. You reconstitute with bacteriostatic water and inject subcutaneously, usually into the abdomen or thigh.
Here's the thing about dosing sources: because TB-500 has no FDA approval, the protocols floating around come from animal research (Malinda KM et al., Journal of Investigative Dermatology, 1999), small clinical case series, and extrapolation by prescribers who've been working with compounded peptides for years. Not large randomized human trials. The molecule appears to have a relatively long systemic distribution half-life (Crockford D et al., Annals of the New York Academy of Sciences, 2010), which is why weekly maintenance dosing works instead of daily pinning.
Loading Phase: Why Front-Load and How
Most compounded telehealth protocols look like this during loading:
- Dose: 2 to 2.5 mg
- Route: subcutaneous injection
- Frequency: twice weekly, typically Monday/Thursday or Tuesday/Friday spacing
- Duration: four to six weeks
The idea is simple: saturate tissue concentrations before dropping to a lower frequency. Think of it like priming a wall before you paint. Some prescribers shorten loading to four weeks for a defined soft-tissue issue (a partially torn rotator cuff, a lingering hamstring strain). Others push to eight weeks for chronic, stubborn presentations.
A gentler on-ramp. For patients new to peptide injections or who tend to be sensitive to novel compounds, some clinicians start at 1 mg twice weekly for two weeks, then step up to 2 mg twice weekly. That's a clinical judgment call, not something backed by a controlled trial.
Maintenance: Holding the Line
After loading, the protocol typically simplifies:
Get provider-reviewed GLP-1 therapy
Side effects are manageable with the right support. A licensed provider can adjust your dose when you need it.
Start Free Assessment →- Dose: 2 mg
- Route: subcutaneous
- Frequency: once weekly
- Duration: six to twelve weeks before a planned break
Some people cycle off entirely after loading if the problem that brought them in has resolved. Others maintain for several months under their prescriber's supervision. There's no single right answer because there's no Phase III endpoint telling us what "optimal duration" looks like.
Reconstitution Math (the Part Everyone Overthinks)
This is where Derek's call came from, and where most of the confusion lives. So let's lay it out plainly.
5 mg vial + 2 mL bacteriostatic water = 2.5 mg/mL (or 0.25 mg per 0.1 mL)
On a U-100 insulin syringe (each "unit" = 0.01 mL):
- 0.5 mg = 20 units
- 1 mg = 40 units
- 2 mg = 80 units
- 2.5 mg = 100 units (full 1 mL barrel)
10 mg vial + 2 mL bacteriostatic water = 5 mg/mL (or 0.5 mg per 0.1 mL)
- 1 mg = 20 units
- 2 mg = 40 units
- 2.5 mg = 50 units
The tradeoff is straightforward. More water means a larger injection volume but easier precision when drawing your dose. Less water means a smaller, more concentrated shot. Some people find lower volume more comfortable; others find higher volume easier to measure accurately. Pick whichever works for you and be consistent.
Bacteriostatic water vs. sterile water: Bacteriostatic water contains 0.9% benzyl alcohol, which preserves the solution for multiple draws over roughly 28 days when refrigerated. Sterile water has no preservative and should be treated as single-use. For a multi-dose vial, bacteriostatic water is the standard choice.
Where and How to Inject
Standard subcutaneous sites:
- Lower abdomen (rotate at least two inches from the navel)
- Outer thigh
- Upper outer buttock
- Back of the upper arm
Technique is bog-standard subQ. Pinch the skin, insert a 29 to 31 gauge insulin needle at 45 to 90 degrees (depending on body composition), depress the plunger slowly, withdraw, apply gentle pressure with clean gauze.
Rotate your sites. This isn't optional if you're doing twice-weekly injections for a month or more. Nobody wants a constellation of irritated injection spots.
You'll occasionally hear people suggest injecting near the problem area, like close to an injured shoulder. The reasoning sounds intuitive, but TB-500 distributes systemically (Goldstein AL et al., Trends in Molecular Medicine, 2005). Whether proximity to the injury site adds local benefit is anecdotal at best. Inject wherever is comfortable and accessible.
Storage, Stability, and the "Don't Shake It" Rule
- Before reconstitution: refrigerate lyophilized vials at 2 to 8°C.
- After reconstitution: refrigerate and use within approximately 28 days.
- Never freeze reconstituted peptide.
- Never shake the vial vigorously. Peptide chains can be sheared by aggressive agitation, like snapping spaghetti by shaking the box too hard. Swirl gently, or just let the powder dissolve on its own (it usually takes a few minutes).
Cycling: When to Stop and When to Reassess
A common cycling pattern:
- Loading phase: four to six weeks
- Maintenance phase: six to twelve weeks
- Break: four to eight weeks
- Reassess with your prescriber
We don't have long-term human safety data on continuous TB-500 use. Planned breaks are a conservative practice, not a proven requirement. But "we don't have data saying continuous use is dangerous" is not the same thing as "continuous use is fine." The boring truth is that nobody knows yet, and erring on the side of cycling off is the more cautious move.
Body Weight Scaling and Stacking
Body weight: Some practitioners dose by mass, roughly 0.03 to 0.05 mg/kg twice weekly during loading. For a 70 kg person, that lands squarely in the 2 to 2.5 mg range. A 100 kg person trends toward the upper end. Most protocols don't explicitly scale by weight because the standard range accommodates a fairly wide body-mass spectrum, but it's worth mentioning to your prescriber if you're well outside the average.
Stacking with BPC-157: TB-500 is frequently paired with BPC-157, particularly for soft-tissue recovery. The two peptides operate through different mechanisms, and there's no published evidence of pharmacokinetic interference between them (Crockford D et al., 2010). That said, stacking decisions belong to your prescriber, not a Reddit thread. (For more context, see the TB-500 vs BPC-157 comparison and the gut-healing stack article on this site.)
FAQ
Is there an "official" TB-500 dose?
No. TB-500 has no FDA-approved indication, which means no label dose exists. The protocols described here are drawn from research literature, animal studies, and clinical practice within compounding telehealth.
How long until I notice anything?
Timelines vary quite a bit. Some patients report perceived changes within two to three weeks. Others complete a full cycle and report nothing subjective. The research literature (Malinda KM et al., 1999) documents measurable biological activity, but individual perceptible response is not guaranteed.
Can I dose more than twice a week during loading?
Some protocols use three times weekly for the first two weeks. No controlled-trial data shows this outperforms twice-weekly dosing, and it increases total exposure without a clear upside. My honest opinion: stick with twice weekly unless your prescriber has a specific reason to push the frequency.
Does TB-500 need to be injected near the injury site?
Not really. The peptide distributes systemically. Injecting near the site of concern is a preference, not a pharmacological necessity.
What if I miss a dose?
Take it when you remember, then resume your regular schedule. Don't double up.
How do I know my reconstitution math is correct?
Use the formulas above, or ask your prescribing pharmacy. If the injection volume looks surprisingly large or small, double-check before injecting. A simple calculator and ten seconds of math can prevent a dosing error.
Can I travel with reconstituted TB-500?
Keep the vial cold (an insulated pouch with an ice pack works) and carry your prescription documentation. Reconstituted peptide that breaks the cold chain for extended periods should be discarded.
Internal Links
- Hub: TB-500 overview
- Pillar: Peptide therapy overview
- Product: TB-500 product page
- Sibling: TB-500 vs BPC-157
- Sibling: TB-500 side effects
- Sibling: TB-500 cycling protocols
---
Disclaimer: TB-500 (thymosin beta-4 fragment) is not approved by the FDA for any indication. Compounded TB-500 is prepared for individual patients through licensed compounding pharmacies based on prescriber clinical judgment. The content above is educational and is not medical advice. Research-stage peptides should only be used under the supervision of a qualified prescriber. Individual results vary.