Synthol is one of the most controversial substances used in bodybuilding. It was designed in the early 90s by the german inventor and bodybuilder, Chris Clark. When it hit the market for the first time, it was regarded with mistrust and skepticism. Most of the criticisms of the product were moral, being an injectable agent for local muscle enlargement; can produce great results right away, but these results are 100% artificial. This means that the product is purely cosmetic. Doesn't increase strength or other muscle capacitys and the gains are not real muscles. The best comparison would be with a homemade cosmetic surgery.
There is no active ingredient, but only an oily substance that the body has difficulty metabolize. How it works is very simple. The solution is injected into a small muscle group (biceps, calves, etc.) and it will remain there for a long time, the body not being able to eliminate it. It will remain for so long in that muscle group that in the end will be encapsulated between the muscle fascias. With multiple injections, a large deposit of the solution will accumulate in the muscles, increasing their size. It will take years until the body can totaly eliminate the substance, which gives the impression of permanent muscles. Increases of 3 cm Can be seen in the muscles where it is injected.
At first, it was said that Synthol contains a synthetic oil that is impossible to duplicate. But being analyzed in detail, it showed that, in fact, contains a mixture of C8-C12 fatty acids (medium chain triglycerides). This oil is mixed with small amounts of lidocaine, a local anesthetic, to reduce pain when is injected. It also contains alcohol for the antimicrobial effect. In other words it is a injectable solution of triglycerides, which is much cheaper than Synthol; but the myth created around it has increased its price.
Currently there are numerous products like Synthol, each with a different name. In some countries is sold at the supplements shops as topical oils for bodybuilding competitions; those oils that bodybuilders rub on their bodyes for competitions to highlight the muscle definition.
Injecting Synthol in large muscle groups leads to an unpleasant aspect, knots and an uneven look. Therefore those who use it generally inject it in the biceps, triceps, shoulders and calves. Standard procedure is to inject 1 ml of substance deep in the target muscle group. The process is repeated daily for a week, maybe 10 days. If the desired effects don;t show the dose is increased to 2.5 ml - 3 ml, also for one week. Then one injection is made every 1-2 weeks maximum. Although the effects are not permanent, they can be maintained for a good period of time, giving the impression that those muscles are there permanently.
This practice is not without risks. Long-term effects include infections, muscle tear and abscesses. Also, if you have the misfortune to hit a vein and inject the solution into it, many risky complications can ahppen depending on where the substance goes (lungs, heart, brain). There are too many unanswered questions for this product to be recommended.
But despite the risks, many are using Synthol.
UPDATE: Due to abuse many complications occurred. The Internet is full of pictures and videos of guys with exploded arms or severe infections. Moral: do not use Synthol!