Sustanon

Testosterone

Sustanon

Sustanon is a sterile oil-based injectable preparation combining four testosterone esters of differing chain length in a single formulation, presented at a total of 250 milligrams per millilitre in a 10 mL multiple dose vial. The blend is engineered so that the esters release sequentially, producing a rapid onset followed by sustained serum levels from one administration.

Composition of the Blend

Each millilitre contains testosterone propionate 30 mg, testosterone phenylpropionate 60 mg, testosterone isocaproate 60 mg and testosterone decanoate 100 mg. All four are esters of the same parent hormone; after hydrolysis each liberates identical testosterone, so the blend differs from a single-ester preparation only in the shape of its release curve, not in the substance delivered.

Sequential Release

Ester chain length governs the rate at which each component leaves the intramuscular depot. The three-carbon propionate is mobilised within hours, phenylpropionate and isocaproate follow over the first several days, and the ten-carbon decanoate sustains serum concentrations for a fortnight or more. The overlapping profiles smooth the peaks and troughs characteristic of single-ester administration.

Pharmacokinetic Profile

The effective half-life of the blend is approximately 15 to 18 days, governed by the slowest component. Serum testosterone rises within 24 to 48 hours of administration through the action of the short esters and is then maintained by the longer ones. The urinary detection window for metabolites extends to approximately 3 months.

Mechanism of Action

Testosterone liberated from all four esters binds the cytoplasmic androgen receptor; the hormone-receptor complex translocates to the nucleus and engages androgen response elements on target DNA, upregulating transcription of genes governing structural protein synthesis and nitrogen retention in skeletal muscle. Peripheral aromatisation to oestradiol and 5-alpha reduction to dihydrotestosterone occur as with any testosterone preparation.

Manufacturing and Sterility

Each production lot is released against the complete pharmaceutical testing protocol, with HPLC quantification of all four esters individually against label claim, purity analysis with a specification of not less than 98 percent, sterility testing in accordance with USP <71>, bacterial endotoxin quantification by LAL assay below 0.25 EU/mL, and particulate matter inspection in accordance with USP <788>. A Certificate of Analysis is issued for every lot.

Quality Assurance

Every batch of Sustanon produced by Biomedica undergoes the complete pharmaceutical release testing protocol before distribution. This includes HPLC compound identity confirmation and purity analysis (specification: ≥98%), concentration verification (specification: ±5% of label claim), sterility testing per USP <71>, bacterial endotoxin quantification by LAL assay (specification: <0.25 EU/mL), and particulate matter inspection per USP <788>. A Certificate of Analysis is issued for every production lot.

Authentication

Each unit of Sustanon carries a unique authentication code on its outer packaging. This code can be verified instantly on our Authentication page to confirm the product is genuine Biomedica stock.