Testosterone Cypionate Description
Testosterone Cypionate Injection, for intramuscular injection, contains Testosterone Cypionate which is the oil-soluble 17 (beta)- cyclopentylpropionate ester of the androgenic hormone testosterone.
Testosterone Cypionate is a white or creamy white crystalline powder, odorless or nearly so and stable in air. It is insoluble in water, freely soluble in alcohol, chloroform, dioxane, ether, and soluble in vegetable oils.
The chemical name for Testosterone Cypionate is androst-4-en-3-one, 17-(3-cyclopentyl-1-oxopropoxy)-, (17ß)-. Its molecular formula is C27H40O3, and the molecular weight 412.61.
Testosterone Cypionate – Clinical Pharmacology
Endogenous androgens are responsible for normal growth and development of the male sex organs and for maintenance of secondary sex characteristics. These effects include growth and maturation of the prostate, seminal vesicles, penis, and scrotum; development of male hair distribution, such as beard, pubic, chest, and axillary hair; laryngeal enlargement, vocal cord thickening, and alterations in body musculature and fat distribution. Drugs in this class also cause retention of nitrogen, sodium, potassium, and phosphorous, and decreased urinary excretion of calcium. Androgens have been reported to increase protein anabolism and decrease protein catabolism. Nitrogen balance is improved only when there is sufficient intake of calories and protein
Testosterone esters are less polar than free testosterone. Testosterone esters in oil injected intramuscularly are absorbed slowly from the lipid phase; thus, Testosterone Cypionate can be given at intervals of two to four weeks.
Testosterone in plasma is 98 percent bound to a specific testosterone-estradiol binding globulin, and about 2 percent is free. Generally, the amount of this sex-hormone binding globulin in the plasma will determine the distribution of testosterone between free and bound forms, and the free testosterone concentration will determine its half-life.
About 90 percent of a dose of testosterone is excreted in the urine as glucuronic and sulfuric acid conjugates of testosterone and its metabolites; about 6 percent of a dose is excreted in the feces, mostly in the unconjugated form. Inactivation of testosterone occurs primarily in the liver. Testosterone is metabolized to various 17-keto steroids through two different pathways.
The half-life of Testosterone Cypionate when injected intramuscularly is approximately eight days.
In many tissues the activity of testosterone appears to depend on reduction to dihydrotestosterone, which binds to cytosol receptor proteins. The steroid-receptor complex is transported to the nucleus where it initiates transcription events and cellular changes related to androgen action.
Indications and Usage for Testosterone Cypionate
Testosterone Cypionate Injection is indicated for replacement therapy in the male in conditions associated with symptoms of deficiency or absence of endogenous testosterone.
1. Primary hypogonadism (congenital or acquired )-testicular failure due to cryptorchidism, bilateral torsion, orchitis, vanishing testis syndrome; or orchidectomy.
2. Hypogonadotropic hypogonadism (congenital or acquired )- gonadotropin or LHRH deficiency, or pituitary-hypothalamic injury from tumors, trauma, or radiation.
Safety and efficacy of Testosterone Cypionate Injection in men with “age-related hypogonadism” (also referred to as “late-onset hypogonadism”) have not been established.
- Known hypersensitivity to the drug
- Males with carcinoma of the breast
- Males with known or suspected carcinoma of the prostate gland
- Women who are or who may become pregnant
- Patients with serious cardiac, hepatic or renal disease
Store at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature]. Protect from light.
10 mL Vial
For intramuscular use only