Testosterone Cypionate (1000mg/5mL)
Testosterone Cypionate (1000mg/5mL) is part of a prescriber-directed hormone or endocrine protocol. It should be selected based on symptoms, diagnosis, labs when appropriate, route preference, contraindications, and ongoing monitoring.
Testosterone Cypionate 1000 mg/5 mL (200 mg/mL) is a compounded intramuscular injectable solution of testosterone cypionate, a long-acting esterified androgen. The cypionate ester at the 17β-carbon position increases lipid solubility and slows hydrolysis after injection, providing sustained testosterone release for up to 2–4 weeks. Testosterone cypionate is the most widely used injectable testosterone formulation for male hypogonadism. Genesis Compounding prepares this as a prescription-only, patient-specific 503A compounded preparation and it is not FDA-approved as a compounded product.
| Active Ingredient | Pharmacologic Role |
|---|---|
| Testosterone Cypionate 200 mg/mL (1000 mg/5 mL) | Long-acting esterified androgen that releases free testosterone upon hydrolysis in depot, restoring eugonadal testosterone levels over a 1–4 week dosing interval. |
Administered by deep intramuscular (IM) injection, typically into the gluteal muscle (ventrogluteal or dorsogluteal) or the vastus lateralis (outer thigh). Use an appropriate needle length and gauge for deep IM injection. Rotate injection sites with each administration. The 5 mL multi-dose vial contains 1000 mg; individual doses are drawn per prescriber instruction. Aspirate prior to injection per current institutional technique. Injection volume per dose should generally not exceed 3 mL per site.
Standard testosterone cypionate dosing for adult male hypogonadism: 50–400 mg IM every 2–4 weeks. Common clinical practice often favors more frequent, lower-dose administration (e.g., 100 mg every 7–10 days) to minimize peak-to-trough fluctuations in serum testosterone.
- Measure serum testosterone at mid-interval (midway between injections) to assess trough and adjust dosing accordingly.
- Target mid-interval testosterone in the low-to-mid normal range (approximately 400–600 ng/dL).
- The prescriber determines all dosing parameters; do not self-adjust dose or frequency.
- Testosterone Cypionate: After IM injection, the cypionate ester is gradually hydrolyzed by plasma and tissue esterases, releasing free testosterone into systemic circulation. Free testosterone diffuses into target cells and binds the intracellular androgen receptor (AR). The testosterone-AR complex translocates to the nucleus, dimerizes, and binds androgen response elements (AREs) to regulate gene transcription governing protein anabolism, erythropoiesis, bone mineral density, negative HPG-axis feedback, and secondary sex characteristics. Peripheral conversion to DHT (5α-reductase) and estradiol (aromatase) also contributes to physiologic effects.
Testosterone cypionate injection is the standard-of-care long-acting androgen for male hypogonadism (primary and secondary), including Klinefelter syndrome, testicular failure, and pituitary/hypothalamic dysfunction. Monitoring is essential due to the large peak-to-trough variation with every-2-to-4-week dosing.
Monitoring parameters:
- Serum total testosterone at mid-interval
- Hematocrit every 3–6 months (reduce or hold dose if Hct >54%)
- PSA at baseline and annually in men ≥40 years
- Lipid panel and liver function as clinically indicated
- Bone mineral density in patients with long-standing hypogonadism
- LH/FSH suppression is expected with exogenous testosterone—do not use to assess HPG axis function during treatment
Contraindications:
- Known or suspected carcinoma of the prostate or male breast
- Pregnancy (virilization of female fetus)
- Hypersensitivity to testosterone cypionate or cottonseed oil (vehicle)
- Serious hepatic disease
Warnings & Precautions:
- Polycythemia (erythrocytosis): monitor hematocrit; dose reduction or therapeutic phlebotomy may be required
- Venous thromboembolism: increased risk with elevated hematocrit
- Cardiovascular events: increased risk of non-fatal MI and stroke—use caution in patients with established CVD
- Edema and fluid retention: may exacerbate heart failure, renal failure, or hepatic cirrhosis
- Suppression of spermatogenesis: significant fertility impairment with prolonged use
- Neuropsychiatric effects: mood swings, aggression, depression
- Schedule III controlled substance—abuse and dependence potential
Drug Interactions:
- Warfarin: androgens potentiate anticoagulant effect; frequent INR monitoring required
- Insulin and oral hypoglycemics: testosterone may reduce blood glucose
- Corticosteroids: additive fluid retention
Common Side Effects: Injection site pain and induration, acne, oily skin, increased hematocrit, mood changes, gynecomastia (via aromatization to estradiol), testicular atrophy, and suppression of sperm production.
Store multi-dose vials at room temperature (15–30°C / 59–86°F). Protect from light. Do not freeze. Testosterone cypionate is prepared in oil (cottonseed oil); if crystals form at low temperatures, warm gently and mix before use. Use within the beyond-use date established by Genesis Compounding. Discard remaining contents after the BUD.
How often will I receive this injection?
Dosing frequency is prescribed individually—commonly every 1–2 weeks, though every 2–4 weeks is the FDA-labeled interval. More frequent lower doses reduce the wide peaks and troughs that can cause mood and energy fluctuations.
Why does my hematocrit need to be checked?
Testosterone stimulates red blood cell production. If hematocrit rises too high (above ~54%), the blood becomes too thick, raising the risk of blood clots and stroke. Lab monitoring allows your prescriber to adjust dosing before this becomes a problem.
Will this affect my fertility?
Yes. Exogenous testosterone suppresses LH and FSH, reducing sperm production. Men seeking to preserve or restore fertility should discuss alternatives (such as enclomiphene or hCG co-therapy) with their prescriber.
Is this FDA-approved?
Testosterone cypionate injection is FDA-approved as a branded product (Depo-Testosterone®). This compounded 1000 mg/5 mL preparation is a patient-specific 503A compounded preparation by Genesis Compounding and is not independently FDA-approved.
What should I do if I miss a dose?
Contact your prescriber for guidance. Do not double-dose. Administer the missed injection as soon as instructed, then resume the regular schedule.
Clinical References
Authoritative sources reviewed in preparing this clinical summary. Provided for prescriber reference; not a substitute for the prescriber’s clinical judgment.