PRPIX-100

Testosterone propionate, sold under the brand name Testoviron among others, is an androgen and anabolic steroid (AAS) medication which is used mainly in the treatment of low testosterone levels in men. It has also been used to treat breast cancer in women. It is given by injection into muscle usually once every two to three days.

Side effects of testosterone propionate include symptoms of masculinization like acne, increased hair growth, voice changes, and increased sexual desire. Testosterone supplementation is also known to reduce the threshold for aggressive behavior in men. The drug is a synthetic androgen and anabolic steroid and hence is an agonist of the androgen receptor (AR), the biological target of androgens like testosterone and dihydrotestosterone (DHT).  It has strong androgenic effects and moderate anabolic effects, which make it useful for producing masculinization and suitable for androgen replacement therapy. Testosterone propionate is a testosterone ester and a relatively short-acting prodrug of testosterone in the body. Because of this, it is considered to be a natural and bioidentical form of testosterone.

Testosterone propionate was discovered in 1936 and was introduced for medical use in 1937. It was the first testosterone ester to be marketed, and was the major form of testosterone used in medicine until about 1960. The introduction of longer-acting testosterone esters like testosterone enanthate, testosterone cypionate, and testosterone undecanoate starting in the 1950s resulted in testosterone propionate mostly being superseded.  As such, it is rarely used today.  In addition to its medical use, testosterone propionate is used to improve physique and performance. The drug is a controlled substance in many countries and so non-medical use is generally illicit.

Medical uses

Testosterone propionate is used primarily in androgen replacement therapy. It is specifically approved for the treatment of hypogonadism in men, breast cancer, low sexual desire, delayed puberty in boys, and menopausal symptoms.

 Androgen replacement therapy formulations and dosages used in men 
 Androgen replacement therapy formulations and dosages used in women 
 Androgen/anabolic steroid dosages for breast cancer 

Available forms

Testosterone propionate is usually provided as an oil solution for use by intramuscular injection. It was also previously available as an 30 mg or 50 mg aqueous suspension. Buccal tablets of testosterone propionate were previously available as well.

Side effects

Side effects of testosterone propionate include virilization among others.

Testosterone propionate is often a painful injection, which is attributed to its short ester chain.

 Androgenic vs. anabolic activity ratio
of androgens/anabolic steroids 
Medication Ratioa
Testosterone ~1:1
Androstanolone (DHT) ~1:1
Methyltestosterone ~1:1
Methandriol ~1:1
Fluoxymesterone 1:1–1:15
Metandienone 1:1–1:8
Drostanolone 1:3–1:4
Metenolone 1:2–1:30
Oxymetholone 1:2–1:9
Oxandrolone 1:3–1:13
Stanozolol 1:1–1:30
Nandrolone 1:3–1:16
Ethylestrenol 1:2–1:19
Norethandrolone 1:1–1:20
Notes: In rodents. Footnotes: a = Ratio of androgenic to anabolic activity. Sources: See template.

Testosterone propionate is a prodrug of testosterone and is an androgen and anabolic–androgenic steroid (AAS). That is, it is an agonist of the androgen receptor (AR).

Pharmacokinetics

Testosterone propionate is administered in oil via intramuscular injection. It has a relatively short elimination half-life and mean residence time of 2 days and 4 days, respectively. As such, it has a short duration of action and must be administered two to three times per week.

Intramuscular injection of testosterone propionate as an oil solution, aqueous suspension, and emulsion has been compared.