Tetrahydrogestrinone (THG) Steroid profile

Tetrahydrogestrinone (THG), sometimes known as "The Clear," is a synthetic, orally active anabolic-androgenic steroid. Unlike other anabolic steroids, which are primarily used in veterinary medicine, THG has not been licensed or sold for any clinical application. This chemical is classified as a designer drug, closely linked to the illegal anabolic steroids trenbolone and gestrinone.

It was developed by Patrick Arnold THG and has by utilized by various high-profile sportsmen like Marion Jones, Barry Bonds, and Dwain Chambers. THG is largely regarded as the first designer steroid in the sporting world.

THG is essentially an oral version of the anabolic steroid Nandrolone. It has several benefits, including increased lean muscle mass and strength. In contrast to other anabolic steroids, THG also forms strong bonds with the glucocorticoid receptor. This effect may cause additional weight loss, but it is also likely to cause additional side effects such as immunosuppression that are not seen with most other steroids.

Despite its performance-enhancing effects, the use of THG carries significant risks. The effects and risks of THG use are not well understood because its synthesis is often done secretly. Known side effects include liver damage, cardiovascular issues, and changes in mood and behavior.

Effective Dose (Men): 2-5 mg/day Anabolic/Androgenic Ratio: High/Moderate.

Structure of THG

Structure of THG

Tetrahydrogestrinone (THG) is a synthetic anabolic-androgenic steroid (AAS) containing a core complex of four hexagonal carbon rings, which all steroids have. The chemical groups connected to the perimeter of this core ring complex give each steroid, including THG, its own identity.
THG was infamously termed the "undetectable" anabolic steroid because of its unusual structure, which allowed it to pass normal drug testing.

How THG Works

Tetrahydrogestrinone (THG) is a powerful performance-enhancing drug because of the way it functions. THG works by entering a cell's nucleus and attaching itself to the androgen receptor at the ligand binding pocket.

Proteins called androgen receptors react to androgens, which are hormones that are essential for masculine characteristics and sexual behaviour. These receptors allow THG to bind, which triggers androgenic and anabolic processes.

The metabolic process that creates larger molecules from smaller ones, including muscular tissue synthesis, is referred to as anabolic functions. In contrast, androgenic functions are in charge of the development and maintenance of masculine traits.

By activating these functions, THG can enhance athletic performance by promoting muscle growth and increasing strength. But understand this too, the use of THG also comes with significant health risks, including liver damage, cardiovascular issues, and changes in mood and behavior.

Effects and Usage

Effects and Usage

THG was found to be a new steroid that was used illegally to enhance sports performance. Its structure is similar to Trenbolone's and closely connected to that of gestrinone, a 19-nor progestin. Since THG was never commercialized, nothing is known about its hormonal characteristics.

Unlike other anabolic steroids, THG has the special ability to bind the glucocorticoid receptor robustly. Further weight reduction might result from this impact, but it also has the potential to have unintended adverse effects including immunosuppression that are uncommon with most other steroids.

In addition to the previously listed adverse effects, using AAS like THG might cause withdrawal symptoms when the medication is stopped. These symptoms are very similar to those observed in subjects with age-related testosterone decline, including increased fat storage and loss of muscle mass.

Effects of Tetrahydrogestrinone (THG)

The powerful and useful steroid tetrahydrogestrinone (THG) is well-known for its ability to improve performance. Its structure is similar to Trenbolone's and closely connected to that of gestrinone, a 19-nor progestin. Its effects are not well known, and there have been few thorough investigations on its hormonal qualities.

Performance Enhancement

THG is mostly used by athletes since it can improve their performance. Strength and lean muscular mass are known to grow with it. Because of this, even though using it has serious consequences, sportsmen seeking a competitive edge frequently choose to use it.

Binding Affinity

Unlike the majority of other anabolic steroids, THG has a high affinity for binding to the glucocorticoid receptor. Further weight reduction might result from this impact, but it also has the potential to have unintended adverse effects including immunosuppression that are uncommon with most other steroids.

THG as a Performance-Enhancing Drug

THG has various advantages, making it an appealing alternative for people wishing to improve their athletic performance. One of the most important impacts of THG is its capacity to build lean muscle mass. THG promotes muscular tissue development, which can help athletes increase strength and power, which is important in sports that require explosive movements or persistent effort.

In addition to increasing muscle mass, THG also enhances strength. This can be particularly beneficial in sports such as weightlifting, where the ability to lift heavy weights is a key determinant of success.
Another key advantage of THG is its capacity to accelerate recuperation. Intense physical exertion can cause muscular injury, resulting in discomfort and reduced performance.  By enhancing recovery, THG allows athletes to train harder and more frequently, leading to improved performance over time.

Finally, THG reduces catabolism, the process by which the body breaks down muscle tissue for energy. By inhibiting this process, THG helps to preserve muscle mass, making it an effective tool for athletes looking to maintain their strength and physique.

Despite these benefits, it is important to note that the use of THG is not without risks. The drug has been linked to several health issues, including liver damage, cardiovascular problems, and changes in mood and behavior. 

Dosage of THG

THG is a powerhouse when it comes to activating the androgen and progesterone receptors, leaving comparison drugs like Nandrolone or Trenbolone in the dust with its mind-blowing potency, approximately 10 times stronger.

The effective dose for men is typically between 2-5 mg/day. It is not recommended for women due to its potent effects and potential side effects. The half-life and detection time of THG are currently unknown. It is important to note that the use of THG is illegal and it has been involved in several doping scandals, such as the BALCO scandal, where it was one of the most common compounds used for doping.

Side Effects of Tetrahydrogestrinone (THG)

The use of THG is associated with several side effects, including

  • Liver damage
  • Cardiovascular issues
  • Changes in mood and behavior
  • Its binding to the glucocorticoid receptor may also lead to immunosuppression.

Tetrahydrogestrinone (THG), like other anabolic steroids, has a range of potential side effects that can impact users’ health. These side effects are often the result of prolonged use and can include both physical and psychological symptoms.

Physical Side Effects

1- Infertility

One of the most significant side effects of prolonged THG use is infertility. This can affect both men and women who use the drug. The steroid can disrupt the body’s natural hormone balance, leading to fertility issues.

2- Acne and Hirsutism

THG use can also lead to other steroid side effects such as acne and hirsutism. Hirsutism is a condition characterized by unwanted, male-pattern hair growth in women.

3- Increased Lean Muscle Mass and Strength

While these are often the desired effects of THG use, they can also be considered side effects. Increased lean muscle mass and strength can lead to an unnatural and potentially unhealthy body composition if not managed correctly.

Psychological Side Effects

1- Mood and Behavior Changes

As with many steroids, THG can cause changes in mood and behavior. This can include increased aggression, mood swings, and other behavioral changes. These psychological side effects can have a significant impact on a user’s quality of life and relationships.

Other Potential Side Effects

While the above side effects are some of the most commonly reported, it is important to note that the side effects of THG can vary widely between individuals. Factors such as dosage, duration of use, and individual health and genetic factors can all influence the side effects a user may experience.


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