Hormones & TRT/HRT Adjuncts

Testosterone Cypionate

Also known as Depo-Testosterone · Test C · testosterone 17-cypionate

Clinically studiedIntramuscular injectionSubcutaneous injectionFDA-approved as testosterone replacement therapy in men; Schedule III controlled substance in the US; prescription only; banned in sport (WADA)

Testosterone cypionate is a hormone (an androgen), not a peptide. It is an esterified form of the natural male sex hormone testosterone, formulated in oil for intramuscular or subcutaneous injection so that it releases slowly over time. Once injected, the ester is cleaved and free testosterone acts on androgen receptors throughout the body. It is one of the established forms of testosterone replacement therapy (TRT) studied for male hypogonadism.

Studied / used for

Used as replacement therapy for male hypogonadism (low or absent endogenous testosterone)
Studied for symptoms associated with testosterone deficiency such as low libido, fatigue, and reduced muscle mass
Used in protocols addressing delayed puberty in males

Commonly reported side effects

Erythrocytosis (elevated hematocrit/hemoglobin)
Gynecomastia
Acne and oily skin
Testicular shrinkage and suppression of sperm production
Fluid retention
Decreased HDL cholesterol
Injection-site reactions
Mood changes

Clinically studied. Supported by human clinical trials. This reflects the strength of the research base, not effectiveness or a recommendation.

Not medical advice.

This is an educational reference. Peptalk does not recommend, prescribe, endorse, or rate any compound, and provides no dosing information. Do not start, stop, or change any peptide, hormone, supplement, or therapy based on this page. All clinical decisions must be made with your licensed healthcare provider.

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