What Is Testagen? Dosage, Half-Life & How to Track It
Also known as: Lys-Glu-Asp-Gly · KEDG · Khavinson pituitary bioregulator
Testagen is a synthetic tetrapeptide (Lys-Glu-Asp-Gly, or KEDG) studied as an anterior-pituitary-derived bioregulator, with preclinical data pointing to effects on thyroid hormone levels and male reproductive hormones. Protocols run it subcutaneously once daily, titrating from 100 mcg up to 200–300 mcg over 8–12 weeks. The supporting evidence is preclinical, not human trials. Educational information only.
What Testagen is and how it works
Testagen is a synthetic tetrapeptide with the sequence Lys-Glu-Asp-Gly (KEDG), classified as an anterior-pituitary-derived bioregulator — meaning the research it is based on targets the pituitary gland's role in the broader endocrine system, rather than the gonads directly.
Preclinical research describes effects on the pituitary–gonadal axis: normalization of thyroid hormone levels and modulation of male reproductive hormones. As with the rest of this peptide family, the theorized mechanism is epigenetic — short peptide sequences interacting with chromatin to influence gene expression in target tissue, here the pituitary.
It is worth being precise about what "endocrine modulation" means here: this is animal and preclinical data, not a human hormone-panel study. Testagen is not FDA-approved, and there is no clinical trial measuring its effect on testosterone, thyroid, or any other hormone in people.
Typical dosing & reconstitution
Testagen is reconstituted with bacteriostatic water — a 20 mg vial mixed with 3.0 mL gives roughly 6.67 mg/mL, where one U-100 unit is about 66.7 mcg.
The community protocol is a slow subcutaneous titration:
| Phase | Daily dose | Units (U-100) |
|---|---|---|
| Weeks 1–2 | 100 mcg | 1.5 units |
| Weeks 3–4 | 150 mcg | 2.25 units |
| Weeks 5–8 | 200 mcg | 3 units |
| Weeks 9–12 (optional) | 250–300 mcg | 3.75–4.5 units |
The fractional-unit doses (1.5, 2.25, 3.75) are a sign this compound is dosed at a small scale — a 30- or 50-unit insulin syringe reads those increments far more accurately than a standard 100-unit syringe.
Half-life & what it means for frequency
No human pharmacokinetic data exists for Testagen. The once-daily schedule is consistent with how it is used in the preclinical studies behind it, not derived from a measured clearance rate.
Because the proposed effect is on an endocrine axis rather than a fast-acting local target, there's no data suggesting timing precision matters much — consistency across the 8–12-week titration is what the protocol is built around.
What to track & possible side effects
There is no dedicated human safety study for Testagen — hormone-adjacent compounds in general warrant extra caution, and this one has essentially no human tolerability data to lean on.
If you are tracking anything here, it should be the actual outcome you care about — labs (thyroid panel, testosterone) drawn periodically through the protocol — rather than assuming an effect. Log the dose and phase alongside any lab work so you can see whether the numbers move at all.
How to track Testagen in Stackeddd
Testagen's 8–12-week titration is easy to lose the thread on — log each phase and dose so you know exactly where you are, and pair it with any lab work (thyroid, testosterone) you're actually running to see if anything changes. Get the reconstitution right first: fractional-unit doses are unforgiving of measurement error.
Model it yourself · free, no account
Reconstitution Calculator
Model it yourself: enter your vial size and BAC water and the Peptides tab returns concentration and exact units for any dose — the same math built into the Stackeddd app.
Related compounds
Related reading: Peptide reconstitution math: how much BAC water to add
Frequently asked questions
What is Testagen?
Testagen is a synthetic tetrapeptide (Lys-Glu-Asp-Gly, or KEDG) studied as an anterior-pituitary-derived bioregulator affecting the pituitary–gonadal axis. It is not FDA-approved, and the evidence behind it is preclinical.
What is Testagen used for?
Preclinical research links it to thyroid hormone normalization and modulation of male reproductive hormones via effects on the pituitary. There is no human clinical trial confirming these hormonal effects.
How is Testagen dosed?
Protocols run 100–300 mcg subcutaneously once daily, titrating up over 8–12 weeks. A 20 mg vial reconstituted with 3.0 mL of bacteriostatic water gives about 6.67 mg/mL.
Does Testagen affect testosterone levels?
Preclinical research describes effects on male reproductive hormone modulation through the pituitary–gonadal axis, but this comes from animal studies, not human trials — there is no clinical data measuring its effect on testosterone in people.
This is educational information, not medical advice. Doses and protocols above reflect published references and community practice — protocol decisions belong with your prescribing physician. Generic names used throughout. How this reference is built & how the AI is tested →
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