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Bodybuilders and others who want to take a shortcut to bigger muscles may be tempted to inject a compound called synthol directly into their muscles.

While the effects are almost immediate, and muscles balloon up quickly, the injections don’t increase strength and may be quite dangerous.

Aside from giving an unnatural look to muscles, synthol injections can damage muscle tissue and put your cardiovascular health at risk. The injections are also permanent, and the damaged tissue may require surgery to remove.

Read on to learn more about the uses and dangers of synthol injections.

Synthol is 85 percent medium-chain triglyceride (MCT) oil, 7.5 percent lidocaine, and 7.5 percent alcohol.

Lidocaine is a painkiller, and the alcohol helps sterilize the mixture and reduce the risk of bacterial infection. MCTs, which have some health benefits, are usually found in coconut oil and palm oil.

When used for muscle growth, synthol is placed in a syringe and injected deep into the target muscle. Once inside muscle fibers, MCT — the active ingredient of synthol — starts to expand.

Synthol differs from anabolic steroids, which are also used by some bodybuilders to boost muscle size. Anabolic steroids have a legitimate medical purpose in helping treat hormonal imbalances, or conditions such as cancer that can cause muscle loss.

Synthol has no such medical value. While it expands muscle tissue, it doesn’t improve muscle strength. It’s typically injected into the biceps, triceps, deltoids, and calf muscles.

Bodybuilders may try synthol prior to a competition because the effects are almost immediate. However, synthol injections often cause muscles to appear deformed and unnaturally shaped, according to a study of bodybuilders using the substance.

A review of several studies found that synthol use may lead to life-long health complications. Synthol can also leave muscles misshapen and out of proportion to other muscles in the body.

What’s more, research shows that synthol may also cause muscle fibrosis. This painful and potentially irreversible condition causes muscle tissue to become so scarred that it may die and have to be removed surgically.

Synthol can also lead to some serious, potentially life-threatening complications — especially if the compound is injected directly into a vein or artery, or if the syringe injures a nerve during the injection.

Among the more serious dangers of synthol injections are:

  • nerve damage
  • blockage of the pulmonary artery, which supplies blood to the lungs
  • heart attack
  • stroke
  • infectious complications

In addition, injection sites can become infected, causing redness and pus to form.

Despite all the risks, synthol is legal and relatively easy to purchase, especially online.

A study in the Journal of Health Psychology found that the internet contains a considerable amount of content touting the safety and effectiveness of synthol for muscle growth, but less reliable science-based information about synthol’s dangers.

Once synthol takes hold in muscle tissue, it’s never absorbed by the body. Instead, synthol hardens, leaving muscles large, but damaged and not any stronger.

Although injured muscle can be surgically removed, scarring may be permanent. If a large portion of muscle tissue must be removed, it’s possible that muscle strength and function may be compromised.

Because synthol affects muscle and tissue across a broad area when it’s injected, there’s no minimally invasive way to remove it. Surgery is the only option, according to a 2019 study.

A surgeon will first use an MRI to reveal what muscle tissue has been permanently damaged. During the removal procedure, an incision will be made near the affected area.

The surgeon will then remove the damaged tissue — or as much as can be safely taken out — and close the incision.

Synthol, which isn’t a type of steroid, exists for only one purpose — cosmetic muscle enhancement (not muscle strength).

Anabolic steroids, which are synthetic versions of the male sex hormone testosterone, can be prescribed to treat hormonal problems, such as delayed puberty.

Individuals who have cancer, AIDS, or another illness that causes muscle loss also may be good candidates for steroids. Anabolic steroids are also taken by bodybuilders, many of whom misuse them to accelerate muscle growth.

The effects of anabolic steroids

Though synthol and anabolic steroids both can be abused by bodybuilders or other individuals looking for shortcuts to bigger muscles, they carry different risks — and long-term effects.

For example, the muscle-building effects of steroids aren’t permanent. Also, steroids won’t make your muscles look bigger without also lifting weights or engaging in resistance training.

The use of synthol is dangerous, despite what you may read in advertisements online to buy the muscle-enhancing compound.

People who have injected their muscles with synthol just to watch them balloon in size can face short-term and long-term health complications, including surgery to remove muscle tissue harmed by synthol.

If you want to build big muscles safely, work with a trainer on a regimen of aggressive strength training and dietary changes.