BPC-157 vs TB-500

What's the difference between BPC-157 and TB-500?

They're two different lab-made peptides with no shared parts. BPC-157 is a chain of 15 amino acids, reported as a fragment of a protein called BPC that was first isolated from human gastric juice¹. TB-500 is a chain of 7 amino acids that copies one short stretch of thymosin beta-4².

That second point gets mixed up a lot online. Thymosin beta-4 is a natural protein 43 amino acids long. TB-500 is only amino acids 17 to 23 of it, with an acetyl group added at one end². Websites often call TB-500 “synthetic thymosin beta-4”, but FDA says the two are not the same substance². A 2026 review in an orthopedic journal adds that there is no shown biological or clinical equivalence between them¹¹. So trials of full thymosin beta-4 tell you little about TB-500. The TB-500 page covers those trials.

BPC-157 vs TB-500 comparison table

BPC-157 has far more published research than TB-500, but almost all of it is in animals. Neither has had the kind of human trials approved medicines go through.

What do the studies show for BPC-157 and TB-500?

Most of what's published is animal research, and TB-500 has very little even of that. BPC-157 has been studied mainly in rats, usually at 10 mcg/kg or 10 ng/kg of body weight a day. It was injected into the belly or given in drinking water¹. In those studies it reduced gut, liver and tendon damage. FDA's reviewers noted that the studies didn't show bigger doses having bigger effects (a dose-response). They also said the molecular target is unknown and how it works is poorly understood¹.

For BPC-157 in people, the published record is short^1,7:

• 16 people with knee pain who had BPC-157 injected into the knee (2 to 4 mg), in a look back through clinic records with no comparison group.
• 12 women with interstitial cystitis who had 10 mg injected into the bladder wall, with no comparison group.
• 2 healthy adults given 10 mg and then 20 mg by IV, as a safety pilot.
• Two older enema studies (one in healthy volunteers, one in ulcerative colitis) published only as meeting abstracts.

A 2026 systematic review rated the overall human evidence as very low certainty⁷.

For TB-500, FDA found no studies in which it was given to people, and no animal studies testing it for wound healing². In one lab dish test, TB-500 did not help close scratch wounds in cultured fibroblasts (connective tissue cells)². A 2026 rat study, published after FDA's review, used 60 mcg/kg a day and reported better tendon healing scores at 4 weeks⁹.

Why do people combine BPC-157 and TB-500 (the Wolverine stack)?

Both are marketed for healing, and sellers offer them together. FDA found websites selling single vials that contain both peptides, some labeled “research purposes only”¹. Online, the pair is sometimes called the “Wolverine stack” or “Wolverine protocol”².

There is no clinical evidence for the combination. The data that exists is very thin:

• Rats: in the 2026 tendon study, BPC-157 plus TB-500 did no better than either peptide alone⁹.
• People: 4 people in the knee pain chart review had BPC-157 with a peptide the authors called thymosin beta-4. There was no comparison group¹⁰.
• Side effect reports: FDA received a report of a 40-year-old woman who injected a BPC-157 and TB-500 product twice a day. She developed darkening of the skin and gums, which came back when she used it again and stopped when she quit. Because the product had two peptides, FDA couldn't tell which caused it¹.

Are BPC-157 and TB-500 legal or FDA approved?

Neither BPC-157 nor TB-500 is FDA-approved, and neither is part of an approved medicine^1–2. FDA lists both on its page of compounding substances that were nominated and then withdrawn, and notes it has little or no safety information on them³.

On July 23, 2026, FDA's Pharmacy Compounding Advisory Committee reviewed BPC-157 for ulcerative colitis and TB-500 for wound healing⁴. The question was whether pharmacies may use them to make compounded medicines. FDA's own reviewers recommended against both^1–2. FDA says it won't make a final decision until it has considered the committee's advice and finished its reviews⁵. When we checked on November 8, 2026, FDA had not posted minutes or a decision⁴.

Outside the US: FDA found no approved BPC-157 product in any country¹, and no approved TB-500 product in Canada, Australia, the UK or the EU².

In sport: the WADA 2026 Prohibited List names BPC-157 under S0 (non-approved substances) and TB-500 under S2.3 (thymosin-ß4 and its derivatives). Both classes are banned at all times, in and out of competition⁶.

What are the risks of BPC-157 and TB-500?

In people, the risks are largely unknown, because neither peptide has had proper human safety studies. FDA found too little clinical safety information to describe BPC-157's safety, and no human exposure data at all for TB-500^1–2.

FDA's reviewers raised the same concerns for both peptides^1–2:

• Immune reactions. Peptides given by injection can trigger the immune system. Reactions can range from none at all to severe. Neither peptide has been tested for this.
• Impurities and clumping. Making peptides can leave related impurities, and peptides can stick together (aggregate). Both can affect safety.
• Unclear identity. “BPC-157” and “TB-500” are common names, not official drug names. FDA has seen different salts and related compounds sold under the same names.

FDA's adverse event database had 3 reports for injected BPC-157 up to December 2025: an injection site reaction, shortness of breath, and the skin darkening case described above¹. These reports can't prove BPC-157 caused the problem. Compounding pharmacies generally don't report side effects to FDA, so the real number is unknown¹.

How does a BPC-157 and TB-500 blend vial work?

Both peptides dissolve in the same water, so every unit you draw holds a fixed amount of each. Mix a vial with 5 mg of each in 2 mL of bacteriostatic (bac) water, and each peptide is at 2.5 mg/mL. Drawing to the 10-unit line on a U-100 insulin syringe gives 250 mcg of BPC-157 and 250 mcg of TB-500.

If the vial holds different amounts of each, every draw keeps that same ratio. You can't change the amount of one without changing the other. These numbers are math only, not a dose from any study.