Description

Testosterone propionate is a fast-acting form of testosterone, the primary sex hormone in humans. It plays an essential role in the development of male and female reproductive tissues and contributes to the appearance of secondary sexual characteristics, such as increased muscle and bone mass, body hair growth, and overall well-being.

Testosterone is essential for maintaining overall health and preventing conditions such as osteoporosis. In men, insufficient testosterone levels can cause physical frailty and bone loss. In addition to its use in sports to support muscle growth, testosterone propionate has medical applications in the treatment of gender dysphoria,male hypogonadism, and certain forms of breast cancer.

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Mechanism of action

Testosterone propionate acts by binding to androgen receptors and is the precursor of dihydrotestosterone (DHT), a biologically active androgen formed by the action of the enzyme 5α-reductase. DHT has a greater affinity for androgen receptors than testosterone.

The hormone-receptor bond induces changes in gene activity, determining androgenic and anabolic effects. Testosterone can also be converted into estrogen through the process of aromatization. In this context, it is mainly estrogen that activates the negative feedback mechanism, suppressing endogenous testosterone production when exogenous testosterone is administered.

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Medical use

Testosterone is included in the World Health Organization's list of essential medicines, confirming its importance in basic healthcare. Testosterone propionate is used in the treatment of male hypogonadism, gender dysphoria, and specific oncological conditions.

With advancing age, natural testosterone production tends to decline; in these cases, hormone replacement therapy (HRT) may be necessary to maintain hormone levels within the physiological range, improving quality of life, sexual function, and body composition.

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Testosterone propionate in mature men

In men over 35 who experience a decline in overall well-being, it is often recommended to assess testosterone levels. If levels are low, replacement therapy can offer benefits such as reduced fat mass, increased muscle mass, and improved sexual function. Regular monitoring of blood parameters, including lipid profile, estradiol, and prolactin levels, is essential. In individuals who wish to preserve fertility, specific protocols with gonadotropins may be necessary.

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Testosterone propionate in sports

In sports, the main benefit of testosterone propionate is its ability to increase muscle mass and strength. The compound has both anabolic and androgenic effects, promoting protein synthesis, nitrogen retention, joint recovery, and improved oxygen transport in the blood. Sports use requires careful monitoring of hormone levels to manage any side effects related to aromatization.

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Effects

• Increase in muscle mass

• Development of male genital organs and secondary sexual characteristics

• Support for spermatogenesis and male sexual behavior

• Increase in muscle strength

• Positive influence on nitrogen and phosphorus metabolism

• Stimulation of erythropoiesis

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Side effects

• Increase in blood pressure

• Increase in sexual behavior

• Increased tendency for blood clotting

• Water retention (edema)

• Effects of masculinization

• Aggression, irritability, and agitation

• Alopecia (baldness)

• Acne

• Insomnia (rare)

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Profile

• Half-life: approximately 20 hours

• Frequency of injections: every 1–2 days

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Pharmaceutical form

Oily solution for intramuscular injection.

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Contraindications

• Pregnancy

• Known or suspected prostate or breast cancer

• Breastfeeding

• Hypersensitivity to the active substance or to any of the excipients