The following article was written by Ben Greenfield
What is TB-500?
TB-500, or Thymosin Beta 4, is a peptide that naturally occurs in the human body and in animal bodies, and, since it is mostly sold for research purposes and veterinary use, is typically implemented in clinical trials in horses.
Thymosins were discovered in the mid 1960’s, when Allan Goldstein from the Laboratory of Abraham White at the Albert Einstein College of Medicine in New York studied the role of the thymus in development of the vertebrate immune system. Since then, Dr. Goldstein founded a company that creates thymosin alpha 1 for the purpose of increasing immune cell activity, and thymosin beta 4 (TB-500) to promote wound repair and healing.
TB-500 has been used extensively for race horses to prevent adhesions from forming, although it is not a prescription veterinary drug. It’s an injectable peptide with limited human use. Mostly, it’s limited to humans who like to experiment, although reports of human use of thymosin dates back as far as 1974 – when a young girl became the first person to receive injections of thymosin because she was diagnosed without a functioning thymus gland.
TB-500 has been shown to offer many of the same effects of growth hormone (GH), including:
- Increasing strength through muscle growth
- Improving endurance
- Speeding up the healing process for wounds
- Reducing acute/chronic pain and/or inflammation
- Increasing flexibility
- Increasing hair growth
As you learned in the previous article on BPC-157, peptides are two or more amino acids linked together in a chain, and TB-500 is a simply a short peptide fragment of an actual hormone – a hormone called “Thymosin Beta-4”.
TB-500 and Thymosin Beta-4 are not exactly the same, although you’ll often see the two names used interchangeably in the peptide world (AKA broscience bodybuilding forums). It’s much harder to get your hands on true Thymosin Beta-4, whether for research use, equine enhancement, athletic performance enhancement or bodybuilding. But TB-500’s peptide sequence shares most of the properties of Thymosin Beta-4, and it’s more economical to produce, thus easier to find.
Just in case you care about the specifics or you really, really miss high school chemistry class, you can dig into the molecular formula of TB-500 below. It is C212H350N56O78S and has an amino acid sequence of the following
How does TB500 work?
The main functionality of TB500 hinges on the ability to upregulate cell building proteins such as actin, which is a protein that forms (together with myosin) the contractile filaments of muscle cells, and is also involved in motion and metabolism in many other types of cells.. Upregulation of actin allows TB500 to promote healing, cell growth, cell migration and cell proliferation. This not only helps build new blood vessel pathways but also upregulates the type of “good” inflammation that is directly correlated with faster wound healing.
Due to its molecular structure and low molecular weight, TB-500 is very versatile, mobile and possesses the ability to travel long distances through tissues. This means that when targeting injured areas (chronic or acute), TB-500 has the ability to circulate through the body and “find” those areas of injury in order to enhance the healing or growth process. Many users have also noted the added benefits of improved flexibility, reduced inflammation in tendons, re-growth of lost hair, and darkening of grayed hair.
Currently, studies are also being conducted on the ability of TB-500 to heal damaged heart tissue, including “athlete’s heart”, also known as ventricular hypertrophy.
In the past, TB-500 has been used extensively for race horses to prevent muscular adhesions and injuries from forming, although it is not a prescription veterinary drug, and MedivetEquine reports that TB-500 offers a variety of benefits to all mammals, regardless of size, including:
- Promotes rapid surface wound healing with little to no scarring and very little discomfort
- Heals at a cellular level, stem cells are the main ingredient to wound healing and body organ regeneration
- Assists with regeneration of blood vessels
- Has been used to improve diabetes in dogs
- Reduces inflammation of the joints
- Increases stamina levels during longer bouts of endurance
In the majority of humans who experiment with TB-500 injections, TB-500 is most often used for acute injuries or wounds that would heal slow (when you need them to heal fast), or for more chronic injuries where the healing doesn’t seem to be happening.
Where to Get TB-500
You can find TB-500 (often sold under the name Thymosin Beta 4) on several peptide supplier websites. These websites can only legally sell the peptides for research purposes. For example:
When you get your TB-500, it will come in a powder form. Just like BPC-157, you will need to “reconstitute” it by adding bacteriostatic water. Go back and read my article on BPC-157 to get access to a peptide calculator that will help you with the mixing/dosage math. Once your TB-500 is properly mixed, you then draw the dose into an insulin syringe, and inject it intramuscularly, subcutaneously, or intravenously (according to your preference).
Supplies needed for TB-500 injection:
- TB-500 (see sources/links above)
- Bacteriostatic Water
- Alcohol swab
- Insulin syringe
Steps for Mixing TB-500:
- Take the lids off both your bacteriostatic water and TB-500 containers.
- Rub the alcohol swab along the rubber stopper on the TB-500 container, and the top of the bacteriostatic water vial and allow each to air dry.
- Fill the insulin syringe with bacteriostatic water and slowly and carefully inject the syringe of water into the 5mg bottle of TB-500 – being careful to spray the water onto the sides of the container rather than directly into the powder. If you do this three times, you will nearly fill the 5mg bottle of TB-500.
- Your TB-500 is now reconstituted. You will want to keep it in the refrigerator or freezer to preserve it until you’re ready to use it.
Do not let your mixed TB-500 sit at room temperature or in the light or it will go bad. To ensure the highest quality, it needs to be kept out of direct light and at refrigerated or frozen temperatures.
When drawing TB-500 into syringes for injection, turn the bottle upside down slowly and draw the liquid into the syringe smoothly and slowly. When injecting, do so with a smooth, slow motion as well. Peptides are fragile and too much mixing and jostling of the container can damage or reduce the effectiveness of your product.
How to Inject TB-500
TB-500 can be delivered through subcutaneous, intramuscular, or intravenous injections.
Before using any of these methods, use a fresh alcohol swab to clean the rubber stopper of your TB-500 bottle and the area of injection. This will minimize your risks for bacteria and contamination.
Subcutaneous injections – You simply pinch an area of skin and push the needle through it.
Tip: You should inject an area of your body near your actual injury.
Intramuscular injections – These are harder than subcutaneous injections as instead of simply inserting the needle under the skin, the needle must be “stabbed” into the muscle as close to the area you are experiencing pain or injury as possible.
Intravenous injection – The needle is inserted directly into the vein, usually on the wrist, elbow, or back of the hand. This one is pretty tough, and I don’t recommend unless you have medical supervision or really know what you’re doing.
After injecting TB-500, massage the area of injection for about a minute to help work the TB-500 into the tissues and improve the absorption and effectiveness.
The most common dose of TB-500/Thymosin Beta 4 is based on your body weight. For a 200-pound person, the dosage recommendation is about 7.66mg per week for six weeks. This is derived by calculating the human dose based on the recommended dosage of TB-500 for greyhounds (5 mg) according to MediVet (the TB-500 manufacturer).
At the risk of sending you down a broscience rabbit hole, here’s a link to a bodybuilding forum discussion that delves into TB-500 dosage in more detail, along with some practical user experiences.
Side Effects and Risks Of TB-500
You should know that there have been some conflicting research studies about this stuff when it comes to cancer. Some studies suggest that it may contribute to the growth of existing cancer cells, while further data suggests it may inhibit cancer.
Doctors have noticed cancer patients have a higher amount of Thymosin in the affected tissues than other people. So in the early stages of research, doctors assumed that this meant Thymosin may cause cancer. After more research was conducted, it was discovered that the main action of Thymosin Beta 4 was to produce new white blood cells – so its presence in the body in the areas affected by cancer was likely not a cause of the cancer, but instead, a matter of “showing up” in the body where cancer lived to help the body mount an immune system response.
But like most peptides on the market, TB-500 has limited long term studies involving human use. Although I haven’t personally used TB-500 (I can’t, since I compete in WADA sanctioned sports like triathlon and obstacle course racing), from what I’ve seen and heard from bodybuilders and athletes using the peptide, the primary side effect is a temporary sense of lethargy. Also, some people report getting a head rush when injecting TB-500, but report this head rush goes away a few minutes after injecting.
Here’s the deal: peptides are the wild, wild west of supplementation.
Many do not have long term safety studies in humans, but decent track records in animals.
Proceed at your own risk.
But when it comes to healing injuries fast, healing the gut, growing new muscle faster, or getting any of the other benefits I mentioned in this article, it may be worth looking into peptides such as TB-500 or BPC-157.