What is Synthol (site enhancement oil)?

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Synthol is an oil injected directly into a muscle to make it look bigger; it is not a drug that builds muscle.

What is Synthol (site enhancement oil)?
A shot that swells an arm in a short time
In bodybuilding talk, the word 'Synthol' comes up with people whose arms or shoulders swelled like balloons in a short time. What is Synthol, and what happens when it is put into the body?
In short
Oil put inside a muscle
Synthol is an oil injected directly into a muscle to make the muscle look bigger. Because such oils make one part of the body look bigger, they are called 'site enhancement oils' in English. Synthol is one of them.
What it is made of
Mostly oil
Synthol is mostly oil, with a small amount of a numbing drug that reduces pain and some alcohol mixed in. The alcohol is added to sterilize the mixture.
Why it looks bigger
Oil, not muscle, fills the space
When the oil is injected into a muscle, the muscle swells right away by the amount injected. The added size is not grown muscle but the oil that went in. So strength and athletic ability do not increase.
Who uses it and why
Cosmetic purposes, only to change shape
Synthol is mostly used by people who do bodybuilding for 'cosmetic purposes', only to change the body's shape. The aim is to change how big a muscle looks, not its strength.
The oil stays
Oil pockets and scars even years later
Injected oil stays in the muscle for a long time. Even years after injection, pockets filled with oil and hard scar tissue remained inside the muscle. The muscle becomes lumpy and misshapen, and in severe cases it is removed by surgery.
Side effects where it is injected
Pain, wounds that will not heal, nerve damage
At the injection site, long-lasting pain, wounds that do not heal, and infections occur. Nerves can be damaged, and the muscle can lose its function. Scars and loss of muscle function sometimes last for life.
Whole-body risks
Oil traveling through blood vessels to the lungs
Cases have been reported in which injected oil entered the blood vessels and blocked the vessels going to the lungs. Heart attacks, in which a vessel bringing blood to the heart muscle is blocked, and strokes have also been reported.
Risks years later
Too much calcium in the blood
When people who had oil (Synthol or paraffin) put into their muscles years earlier were examined, about one in three had too much calcium in the blood. One cause is that the tissue around the oil lumps makes a form of vitamin D that pushes calcium up. More than one in three had kidney stones.
A common misconception
Is it safe because it is not a hormone?
People who use Synthol are often drawn by the fact that, unlike anabolic steroids, the muscle-building drugs, it is not a hormone (a substance that carries signals in the body) and so lacks their side effects. It is true that Synthol is not a hormone. But side effects of its own that damage muscle and threaten life have been reported.
Summary
Size filled by oil, not muscle
Synthol is an oil injected directly into a muscle to make it look bigger, and it is not a drug that builds muscle. Even though it is not a hormone, side effects that damage muscle and threaten life have been reported. Related terms: anabolic steroids, heart attack, growth hormone drugs.