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Peptide · for horses

Thymogen for horses

Thymogen is a lab-made peptide. It has never been officially tested in horses, and the FDA hasn't approved it for animals. Talk to your vet first, and prefer a seller that shows a lab test.

By the peptidesfor.horse teamStudies checked 13 Nov 2026Sellers checked 28 Oct 2026
At a glance
Tested in horses
No clinical trial
FDA-approved for animals
No
In competition
Not named by FEI
Sellers checked
1
With an outside lab report
0
Lowest price in stock
$99
Safe amount for a pet horse
Unknown
Not named by the FEI does not mean allowed

Thymogen is not named on the 2026 FEI Equine Prohibited Substances List. That does not clear it: the list also covers "any other substance with a similar chemical structure or similar biological effect(s)". Ask the FEI or your federation before you compete. Also check your national federation and any racing rules. Products are sold as "research" and the label won't warn you.

What it is

Thymogen is a two-amino-acid peptide (Glu-Trp) developed in Russia as an immune medicine, listed as an ingredient in some pet oils. It is not an approved drug for any animal.

What the research says

No clinical trial in horses has been published, so nobody can say whether it helps your horse, or what a safe amount would be.

It is not an approved animal drug. Vials sold for animals are usually labelled "research only", which means no one has taken responsibility for giving them to your horse. Ask your vet which tested treatments fit the problem.

The risks

  • 1No clinical trial has tested safety in horses.
  • 2Products aren't checked by the FDA, so the product may not contain what the label says.
  • 3"Research only" labels mean there is no one to call if something goes wrong.
  • 4A positive drug test in competition is possible.

Who sells it, ranked by proof

1 seller sell Thymogen for horses. They’re ranked by what they prove, not by what they pay us. A seller with an FDA warning letter stays listed, with the letter under its name. Sellers label these products “for research”; we list them so you can see who proves what’s in the product.

PetTides

Full Body Support oil (BPC-157 + KPV + Thymogen) · Oil

Reports by email only
$99 to $1494 or 8 oz
Visit seller

Compare the sellers · How we score sellers · How to read a lab test

Questions horse owners ask

Is Thymogen safe for horses?

Nobody knows. No clinical trial in horses has been published, and products aren't checked by the FDA. Talk to your vet before you try anything.

Does Thymogen work for horses?

Nobody can say. Without a clinical trial in horses, there is no good evidence that it helps any horse condition, or that it doesn't.

Is Thymogen legal for horses?

It is not an approved drug for animals. FDA treats a product sold to treat disease in animals without approval as an unapproved drug, and in November 2024 it warned six sellers of seizure products for dogs and cats on those grounds. We found no FDA action aimed at Thymogen for animals, which is not the same as approval.

Can my vet prescribe Thymogen?

Not as an approved medicine, because none exists. Compounding for one animal is a separate route under FDA guidance, with conditions, and we found no vet compounding pharmacy offering it (checked October 2026). Ask your vet which approved options fit your horse.

Sources

  1. PubMed, Thymogen in horses, clinical trials only: no results, checked 13 Nov 2026. Open
  2. FDA, Approved Animal Drug Products (Green Book): Thymogen not listed. Open
  3. FDA warning letters to six sellers of unapproved seizure products for animals, dated 12 Nov 2024. No peptide is named. Open
  4. FEI, 2026 Equine Prohibited Substances List. Open