General Description

Boldenone undecylenate is a veterinary drug used primarily in horses, dogs, and livestock to promote muscle growth and improve physical performance. It exerts its effects by binding to androgen receptors, triggering molecular events that regulate gene expression. This leads to increased protein synthesis and muscle growth. Boldenone undecylenate also has masculinizing effects on male sexual characteristics. Common side effects include changes in behavior, increased aggression, masculinization in female animals, and effects on the reproductive system. Its use as a veterinary drug is supervised by licensed professionals, but it is not approved in all countries and is illegal for human use.

Figure 1. Injection of boldenone undecylenate

Mechanism of action

Boldenone undecylenate exerts its effects through a mechanism of action that is similar to the natural hormone testosterone. It binds to intracellular receptors known as androgen receptors, which are present in various tissues throughout the body. Binding of boldenone undecylenate to the androgen receptors triggers a series of molecular events within the cell. Once bound to the androgen receptor, a complex is formed that translocates to the nucleus of the cell, where it acts as a transcription factor, regulating the expression of specific genes. These genes encode for proteins that are responsible for the physiological effects of boldenone undecylenate, such as increased muscle growth and improved physical performance. The specific molecular mechanisms involved in the action of boldenone undecylenate include the activation of anabolic pathways responsible for protein synthesis and muscle growth. It also has anabolic effects on bone and muscle tissue, leading to improved physical performance. Additionally, boldenone undecylenate has masculinizing effects on male sexual characteristics, such as increasing libido and potency. ¹

Application as veterinary drug

Boldenone undecylenate is used as a veterinary drug primarily in horses, dogs, and other livestock to promote muscle growth, improve physical performance, and enhance overall condition. In horses, boldenone undecylenate is commonly used to enhance physical performance and improve the appearance of muscle tone and condition. It is often injected at low doses as part of a training program to increase muscle mass and strength. Boldenone undecylenate may also be used to treat conditions such as equine metabolic syndrome, a condition characterized by obesity and insulin resistance, in horses. In dogs, boldenone undecylenate is used primarily to promote muscle growth and improve physical characteristics. It is commonly administered as an injectable preparation and may be used in conjunction with other hormones, such as progesterone or estradiol, to achieve the desired effects. Boldenone undecylenate is commonly used in breeding programs and by dog owners to enhance the physical appearance and market value of their pets. The use of boldenone undecylenate as a veterinary drug is typically supervised by a licensed veterinarian or veterinary professional trained in its proper use. It is important to note that the use of boldenone undecylenate as a veterinary drug is not approved in all countries, and its use in humans is illegal and unregulated. ²

Side effect

The most common side effects of boldenone undecylenate include changes in behavior and increased aggression. In horses, this may manifest as restlessness, irritability, and increased desire to fight. In dogs, boldenone undecylenate may cause agitation, hyperactivity, and territorial aggression. These behavioral changes are likely due to the drug's impact on the central nervous system. Another common side effect of boldenone undecylenate is masculinization in female animals. This can result in physical changes such as the development of male-typical genitalia and secondary sexual characteristics. In severe cases, this may lead to infertility in female animals. Boldenone undecylenate can also affect the reproductive system of animals. It may cause changes in the normal menstrual cycle or lead to a complete absence of menstruation (pseudopregnancy). In males, boldenone undecylenate can stimulate the growth of the prostate gland, leading to prostate enlargement and discomfort. ³

Reference

1. El Deib MM, El-Sharkawy NI, Beheiry RR, Abd-Elhakim YM, Ismail SA, Fahmy EM, Saber T, Saber TM. Boldenone undecylenate disrupts the immune system and induces autoimmune clinical hypothyroidism in rats: Vitamin C ameliorative effects. Int Immunopharmacol, 2021, 99:107939.

2. Elmajdoub A, Garbaj A, Abolghait S, El-Mahmoudy A. Evaluation of boldenone as a growth promoter in broilers: safety and meat quality aspects. J Food Drug Anal, 2016, 24(2):284-292.

3. Alm-Eldeen A, Tousson E. Deterioration of glomerular endothelial surface layer and the alteration in the renal function after a growth promoter boldenone injection in rabbits. Hum Exp Toxicol, 2012, 31(5):465-472.