PreclinicalShort bioregulator peptide

Testagen

Lys-Glu-Asp-Gly (KEDG)

Common dose: 0.2–2 mg daily for 10–20 days
Cycle: 2-week course, about every 4 months
Vial sizes: 20 mg
Typical draw: 10 units20 mg with 2 mL, 1 mg

A synthetic four-amino-acid peptide from the Russian bioregulator family, sold for male reproductive health. The chicken studies that tested it describe it as built from pituitary extracts and report thyroid and immune effects.

Evidence. Test-tube, cell and chicken studies only, from Khavinson’s network and a partner group in Chita, mostly in Russian journals. It’s sold for the testes and testosterone, but no study has looked at either, and none has given it to people.

What it’s used for

None of these uses is approved, and none has been tested in people. Here is what each claim rests on.

Testosterone, sperm and libido: No studyUnproven: no published study has tested it on testosterone, sperm, libido or the testes, in animals or people. Its developers list male reproductive function but cite no such study.
Underactive thyroid after pituitary loss: AnimalIn chickens whose pituitary gland was removed, 40 days of it raised thyroid-stimulating hormone and thyroid hormones and restored thyroid structure. Never tested in people or other mammals.
Immune and thymus function: AnimalIn the same chickens it normalized immune and blood-clotting measures and helped restore the thymus. Not tested in people.
Chronic prostatitis: No studySome guides cite a prostatitis study showing a testosterone rise, but no such study of this peptide appears in PubMed.
Aging and gene activity: AnimalIn 2011 and 2013 test-tube studies by its developers, it entered cell nuclei and bound DNA and histones, which they link to gene control in aging. No effect on aging has been measured.

Animal: cell or animal studies only. No study: nothing published supports it.

Every compound’s uses, by body system: evidence map, and by condition: conditions A to Z.

Status

Approval: Not approved as a drug in the US or EU, and no registered medicine containing it was found anywhere.
US compounding: Not nominated for US compounding: it isn’t on FDA’s 503A (May 2026) or 503B (March 2025) bulk substance nomination lists.
European Union: No marketing authorization; no medicine containing Testagen is approved anywhere.
United Kingdom: No marketing authorization (MHRA).
Canada: No marketing authorization; no Testagen product is listed in Health Canada’s Drug Product Database.
Australia: No marketing authorization. Testagen isn’t named in the Poisons Standard (October 2026).
Sport (WADA 2026): Likely banned in sportNot named on WADA’s 2026 list, but its S0 rule bans substances with no current approval by any health authority for human use, at all times.

Category 2 is FDA’s list of bulk substances that may present significant safety risks in compounding. The 503A bulks list adds substances that pharmacies may compound with. Advisory committee votes are advice; FDA makes the final decision. Sport status follows the WADA Prohibited List in force since January 1, 2026; athletes should confirm with their anti-doping organization. Checked October 5, 2026. Status outside the US checked October 7, 2026 against EMA, MHRA, Health Canada and TGA records. By country: EU, UK, Canada, Australia. Status of every compound.

How it works

No receptor or target is known. In 2011 and 2013 lab tests by its developers, this four-amino-acid peptide entered the nucleus of human cells and bound DNA fragments and histones, the proteins DNA wraps around, which they propose changes gene activity. In chickens whose pituitary gland had been removed, 40 days of it raised thyroid-stimulating hormone and thyroid hormones and helped restore the thyroid and thymus. No study has looked at the testes.

AnimalMainly from cell and animal studies; not shown in people.

Not known

Its target is unknown, no study has tested the testes or testosterone it’s sold for, and whether the bird results apply to people is untested.

Protocol

Community

Injected: guides range from 100–300 mcg to 1–2 mg once daily for 10–20 days, about a 20-fold spread. None was tested in people.

Community

A few guides list 5–20 mg a day by mouth, under the tongue or injected, for 10–30 days. No human data test any of these.

Frequency: Once daily during a course
Route: Subcutaneous injection (community)
Cycle: 10–20 day courses, repeated every few months.
2-week course, about every 4 months, shown over 26 weeks

Common protocols

The ways Testagen is most often run, each tagged with where it comes from.

Low-dose injected course

Community

Dose: 100–300 mcg
How often: Once daily
How long: 10 days

The most common guide amount; one guide repeats the course every 4–6 months. Untested in people.

Draw 1–3 units20 mg + 2 mL

Milligram injected course

Community

Dose: 1–2 mg
How often: Once daily
How long: 10–20 days

Other guides. Also untested in people.

Draw 10–20 units20 mg + 2 mL

Oral or under-the-tongue course

Community

Dose: 5–10 mg
How often: Once daily
How long: 10–30 days

A minority of guides. No study has tested any route in people.

Taking it

Where it goes

Subcutaneous, rotating between the abdomen, thigh and upper arm. Published research used cells and chickens, not people.

If you miss a dose

No published guidance. Resume the next day and don’t double up.

Missed doses for every compound

What to expect

During a course
Guides claim better testosterone, libido and sperm health. No study has measured any of these, in animals or people.
Community
40 days (chickens)
In chickens without a pituitary gland, daily doses raised thyroid-stimulating hormone and thyroid hormones and restored thyroid structure.
Animal

Side effects and what to do

Injection-site redness or swelling

Usually mild; rotate sites. Spreading redness, heat or pus means see a doctor.

No side-effect data from people

No study has given it to anyone, so side effects and their rates are unknown.

Allergic reaction (possible with any injected peptide)

Stop and get emergency care for hives, facial swelling or trouble breathing.

Stop and get medical help

Stop and get medical help for hives, swelling of the face or throat, trouble breathing, or a hot, spreading or pus-filled injection site.

Can it cause …?

There are almost no human safety data for Testagen, so most of these can’t be answered either way.

Fast heartbeat or blood pressure changes: No dataNo human data. In chickens it raised thyroid hormones, which can speed the heart, but no heart effects were reported.
Cancer risk: PrecautionUnknown. It’s sold to raise testosterone, which no study has shown; if it did, hormone-sensitive cancers such as prostate cancer could be affected.
TirednessHeadacheNausea or vomitingDiarrhea or constipationDizzinessTrouble sleepingHair lossAcne, rash or skin changesWater retention or swellingJoint or muscle painAnxiety, low mood or irritabilityLow or high blood sugarMore hungerLiver strainKidney problems: No dataNo human data: no study of Testagen in people has been published, so side effects are unknown.

Precaution: a concern that follows from how it works or from a related drug, not measured. No data: no human safety data. A side effect that hasn’t been reported can still happen, especially with long or high-dose use. Any of these across every compound: the side-effect finder.

Who should avoid it

No product label covers Testagen, so these come from human studies and from precautions based on how it works. Most important first.

Thyroid disease or thyroid medicines: PrecautionIn chickens without a pituitary gland it raised thyroid-stimulating hormone and thyroid hormones. Whether it changes thyroid function in people is unknown.
Prostate or other hormone-sensitive cancer: PrecautionIt’s sold to raise testosterone. No study shows that it does, but if it did, hormone-sensitive tumors could be affected.
Pregnancy or breastfeeding: PrecautionNo human safety data exist.
Anyone relying on product quality: PrecautionIt isn’t an approved drug anywhere, so vials have no regulated standard for identity, purity or sterility.

Interactions

No interaction studies have been published, and no product label lists any.

Precaution: follows from how it works or from a related drug, and hasn’t been tested. This isn’t a complete list: a pharmacist or doctor can check a specific medicine or condition. Every documented interaction, by medicine: drug interactions.

Special situations

What’s known about pregnancy, breastfeeding, kidney and liver problems, age and surgery. Where nothing has been studied, the row says so.

Pregnancy: PrecautionNo human or animal pregnancy data, so effects on a pregnancy are unknown.
Breastfeeding: PrecautionNo human data; it isn’t known whether it passes into breast milk.
Kidney problems: PrecautionNot studied in people with kidney disease; how the body clears it is unknown.
Liver problems: PrecautionNot studied in people with liver disease; how the body breaks it down is unknown.
Older adults: PrecautionNo study has given it to older people. In old hens without a pituitary gland its thyroid effects were weaker than in young chickens.
Children and teens: PrecautionNot studied in anyone under 18, and not approved for any age.
Surgery and anesthesia: PrecautionNo data; tell the surgical team about any injected compound.

Precaution: not studied, so the caution follows from how it works or from a related drug. Ages are given as approved or studied; this site never gives doses for children. Across every compound: pregnancy, breastfeeding, kidney disease, liver disease, older adults and surgery.

Tracking and pairing

Worth tracking

Testosterone and thyroid tests (TSH), if used for hormone claims; no study defines an expected change

Often paired with

Usually run on its own.

Human studies

No published human studies of Testagen turned up in our October 2026 review. The evidence note at the top of this page sums up what is known.

Trials under way

No ongoing trial of Testagen is registered, and none has finished recently without publishing its results. Checked on ClinicalTrials.gov, October 7, 2026. Every compound: trials under way.

Limits of the evidence

No study has given Testagen to people, and none has examined the testes, sperm or testosterone. The published work is test-tube and cell studies of DNA binding, computer models, and five studies in chickens without a pituitary gland from a partner group in Chita, mostly in Russian journals, which describe it as a pituitary peptide. Doses, long-term safety and product purity are untested.

Mixing your vial

Vial	Water	Common dose	Draw	Strength	Action
20 mg	2 mL	1 mg	10 units (0.10 mL)	10 mg/mL

20 mg in 2 mL gives 10 mg per mL, so 1 mg is 10 units on a U-100 syringe. Guides using 100–300 mcg doses add more water; 20 mg in 10 mL puts 200 mcg in 10 units.

Dose chart

20 mg vial

Syringe units for common doses at different water volumes. Select a cell to open it in the calculator.

Dose	Water added
Dose	1 mL	2 mL	3 mL
0.1 mg
0.2 mg
0.3 mg
0.5 mg
0.6 mg
1 mg
2 mg

U-100 insulin syringe: 100 units is 1 mL. Draws over 100 units show in mL. Faded values are under 2 units, which is hard to measure. Check that your vial holds the larger volumes.

Datasheet

Half-life: No reliable value has been published.
Type: Peptide, 4 amino acids
Molecular weight: 447.4 g/mol
Formula: C₁₇H₂₉N₅O₉
Sequence: KEDG
Storage before use: Freezer (about −20 °C) for long-term storage.
After mixing or opening: Fridge (2–8 °C); use within about 4 weeks.

Molecule: PubChem CID 123863700 (H-Lys-Glu-Asp-Gly-OH)
Storage: Community Common practice for research peptides; no approved label exists.

Every compound side by side: the half-life chart and the storage chart.

Identifiers

UNII (FDA): None assigned
PubChem CID: 123863700
ATC code: None assigned
Development codes: None; also written KEDG (Lys-Glu-Asp-Gly)
Brand names: None; no medicine containing it is approved anywhere
First described: First reported in 2008 by a Chita group, as a peptide modeled on pituitary extracts; named Testagen by 2011.

Every compound’s numbers: the identifiers table.

Product form and quality

A four-amino-acid peptide, Lys-Glu-Asp-Gly (KEDG). Testagen TDS, a testosterone lotion registered for a US trial, is unrelated despite the name. Vials have no regulated standard for identity, purity or sterility.

Cautions

No study has given Testagen to people, and none has looked at the testes or testosterone.
In chickens without a pituitary gland it raised thyroid hormones; effects on human hormones are unknown.
An unrelated testosterone lotion registered for a US trial is also called Testagen.

Questions

What is Testagen?

How does Testagen work?

Is Testagen FDA-approved?

Not approved as a drug in the US or EU, and no registered medicine containing it was found anywhere. Not nominated for US compounding: it isn’t on FDA’s 503A (May 2026) or 503B (March 2025) bulk substance nomination lists.

What is the usual Testagen dose?

From community reports, not established: Injected: guides range from 100–300 mcg to 1–2 mg once daily for 10–20 days, about a 20-fold spread. None was tested in people. A few guides list 5–20 mg a day by mouth, under the tongue or injected, for 10–30 days. No human data test any of these. These are the amounts sources reference, not recommendations.

How much water do I mix Testagen with?

There’s no single right amount, because the water only sets the strength. With 2 mL of bacteriostatic water in a 20 mg vial, the strength is 10 mg/mL, so 1 mg is 10 units on a U-100 insulin syringe. More water makes small doses easier to measure. The dose chart above shows other volumes.

Who should avoid Testagen?

No product label covers Testagen, so these come from human studies and from precautions based on how it works. Thyroid disease or thyroid medicines: In chickens without a pituitary gland it raised thyroid-stimulating hormone and thyroid hormones. Whether it changes thyroid function in people is unknown. Prostate or other hormone-sensitive cancer: It’s sold to raise testosterone. No study shows that it does, but if it did, hormone-sensitive tumors could be affected. Pregnancy or breastfeeding: No human safety data exist. The “Who should avoid it” section lists 1 more group.

How should Testagen be stored?

Before mixing: Freezer (about −20 °C) for long-term storage. After mixing: Fridge (2–8 °C); use within about 4 weeks. This is common practice; no product label covers it.

Is Testagen banned in sport?

Probably. Not named on WADA’s 2026 list, but its S0 rule bans substances with no current approval by any health authority for human use, at all times.

Has Testagen been studied in people?

No published human studies turned up in our October 2026 review. The evidence note at the top of this page sums up what is known.

How long has Testagen been studied in people?

No data No human studies: no study of Testagen in people has been published.

Does Testagen come in other forms, like a pill or nasal spray?

Animal No human data for any route. Guides inject it under the skin; a few use it by mouth or under the tongue. The chicken studies injected it.

Can you drink alcohol while taking Testagen?

No study No data. No study has looked at Testagen and alcohol together.

Can Testagen be taken with semaglutide or tirzepatide?

No study No study has combined them. No interaction is known, but none has been looked for.

What happens if you take too much Testagen?

No data There’s no label, no overdose data and no human dosing study. Call Poison Help (1-800-222-1222), or emergency services for severe symptoms.

Sources

Fedoreyeva et al., testagen (Lys-Glu-Asp-Gly) and other short peptides enter cell nuclei and bind DNA (Biochemistry (Mosc) 2011) PMID 22117547
Kuznik et al., Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly in chickens without a pituitary gland (Bull Exp Biol Med 2011) PMID 22268052
Khavinson et al., review of peptide regulation of gene expression, naming KEDG as Testagen (Molecules 2021) PMID 34834147

For the protocol details

Kuznik et al., KEDG and AEDG on the thyroid in chickens without a pituitary gland (Bull Exp Biol Med 2008) PMID 19024016
Pateyk et al., KEDG and AEDG on the thymus in young and old birds without a pituitary gland (Bull Exp Biol Med 2013) PMID 23658898

For how it works, who should avoid it and the limits of the evidence

Fedoreyeva et al., short peptides including Lys-Glu-Asp-Gly bind wheat histones (Biochemistry (Mosc) 2013) PMID 23581987
Kuznik et al., pituitary-derived KEDG and AEDG on immunity, clotting and the thyroid in birds (Patol Fiziol Eksp Ter 2010, in Russian) PMID 20731122
Khavinson et al., computer docking of 26 short peptides, including KEDG, to amino acid and peptide transporters (Biomolecules 2023) PMID 36979488

For uses, the side-effect questions, special situations, trials, identifiers and status outside the US

ClinicalTrials.gov search for Testagen (October 8, 2026): only NCT02733133, an unrelated testosterone lotion
FDA Global Substance Registration System search (no record) and PubChem CID 123863700
Health Canada Drug Product Database search (October 8, 2026) and Australian Poisons Standard, October 2026 (F2026L01327)

Doses tagged Community come from public dosing guides and user reports, checked against at least two of them. Those sites aren’t named here because many of them sell peptides or earn commissions on them.

By Vial Guide editorsLast reviewed October 7, 2026

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