Synthol and Site Enhancement Oils: Are They Worth the Risk?

Muscle Growth Myths: Why Synthol Is a Dangerous Trend

Using site enhancement oils like Synthol has become a controversial trend in bodybuilding. Some individuals inject Synthol directly into their muscles to achieve a bulkier appearance without actual muscle gain. While this method may create the illusion of larger muscles, it poses serious health risks and does not enhance strength or performance.

Understanding Synthol: What Is It?

Synthol is a type of site enhancement oil originally developed for cosmetic procedures such as wrinkle reduction and breast augmentation. However, bodybuilders and fitness enthusiasts have adopted it to artificially inflate muscle size. The compound is a mixture of 85% medium-chain triglyceride (MCT) oil, 7.5% lidocaine (a local anaesthetic), and 7.5% benzyl alcohol.

• MCT Oil – Acts as the primary filler to expand muscle tissue.
• Lidocaine – Reduces pain upon injection.
• Benzyl Alcohol – Serves as a sterilizing agent.

When injected, Synthol causes muscles to swell instantly, giving them a fuller look. Common areas for injection include the biceps, triceps, deltoids, chest, and calves. However, this expansion is purely cosmetic and does not improve muscle function.

Why Do Bodybuilders Use Synthol?

Some bodybuilders turn to Synthol as a shortcut to make their muscles appear larger and more defined. The main reasons for using Synthol include:

• Immediate muscle expansion – Results can be seen almost instantly.
• Correcting muscle imbalances – Used to make underdeveloped muscles appear proportionate.
• Aesthetic enhancement before competitions – Some competitors inject Synthol to improve muscle symmetry temporarily.

While Synthol may seem like an easy way to achieve the look of larger muscles, it comes with several risks and side effects that can lead to permanent damage.

How Does Synthol Affect Muscles?

Once injected, Synthol remains in the muscle tissue and is not naturally absorbed by the body. Instead, it hardens over time, causing muscle deformation and potential loss of function. Unlike anabolic steroids, which promote actual muscle growth, Synthol does not enhance muscle strength or performance.

Key Differences: Synthol vs. Anabolic Steroids

Factor	Synthol Injection	Anabolic Steroids
Purpose	Cosmetic muscle enhancement	Muscle growth and strength
Composition	Oil-based compound	Synthetic testosterone
Effect on Strength	No increase in muscle strength	Increases muscle mass & power
Medical Use	No approved medical use	Used for hormonal disorders
Risks & Side Effects	Muscle deformation Infection	Organ damage Hormonal imbalance

Are Synthol Injections Permanent?

Synthol does not break down naturally, and once it settles in the muscles, it stays there unless surgically removed. Over time, the injected muscle may harden, leading to a misshapen and unnatural appearance. In severe cases, the muscle may lose function due to fibrosis, a condition where muscle tissue becomes excessively scarred.

How Can Synthol Be Removed?

The only way to remove Synthol is through surgery. Since it spreads throughout the muscle tissue, minimally invasive procedures are ineffective. Surgeons use MRI scans to locate the damaged areas and then perform an incision to extract as much of the oil and affected tissue as possible. However, if too much tissue is removed, it can compromise muscle function permanently.

Health Risks and Side Effects of Synthol

Synthol injections can cause numerous health problems, ranging from mild discomfort to life-threatening complications.

Common Side Effects

• Muscle Deformation – Injected muscles may appear unnatural and uneven.
• Chronic Pain – Injected areas may become stiff and painful over time.
• Nerve Damage – Improper injections can lead to nerve injuries, affecting movement and sensation.

Serious Health Risks

• Infection: Injection sites may become inflamed and filled with pus.
• Fibrosis: Muscle tissue can become hardened and scarred.
• Pulmonary Artery Blockage: This can lead to respiratory failure if Synthol enters the bloodstream.
• Heart Attack or Stroke: Injecting into a vein can cause deadly complications.
• Septicemia: A life-threatening blood infection can occur.

In 2021, a case study reported that a woman who injected Synthol into her buttocks developed granulomas (clusters of white blood cells), leading to severe health complications such as kidney stones and heart arrhythmia.

The Dangers of DIY Synthol Injections

Some individuals attempt to self-administer Synthol without medical supervision, significantly increasing the risks. Improper injection techniques can cause nerve damage, infections, and life-threatening complications.

Risks of Self-Injection:

• Using unsterilized needles can introduce bacteria into the bloodstream.
• Injecting too much Synthol can cause extreme swelling and tissue necrosis.
• Lack of medical guidance can lead to improper placement and severe complications.

Final Thoughts: Should You Use Synthol?

While Synthol may offer quick muscle enhancement, the long-term consequences far outweigh any short-term benefits. Unlike anabolic steroids, which increase actual muscle mass, Synthol only provides a temporary visual boost without improving strength or performance. The risks, including permanent muscle damage, infections, and life-threatening conditions, make Synthol a dangerous choice.

If you are looking to build muscle effectively, proper training, nutrition, and consistency remain the safest and most effective methods. Consulting a fitness expert or medical professional can help you achieve your muscle-building goals without putting your health at risk.

References

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3. (2019). Available at: https://www.researchgate.net/publication/271703572_Bodybuilders’_accounts_of_synthol_use_The_construction_of_lay_expertise_online (Accessed: 5 March 2025).
4. Madhana, R. M., Gunturu, K., Gopu, P., Kancharla, N. J. and Vedantham, V. (2024) Indian Journal of Pharmaceutical Sciences, ijpsonline. OMICS International. Available at: https://www.ijpsonline.com/articles/cosmetic-abuse-of-site-enhancement-oils-an-insight-review-on-synthol-and-other-targeted-enhancement-oils-5513.html (Accessed: 5 March 2025).
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