Nandrolone Decanoate (Deca-Durabolin)
Also known as Deca, Deca-Durabolin, Nandrolone, 19-nortestosterone
A slow, long-acting 19-nor steroid known for size gains and joint comfort - and for stubborn sexual side effects.
Anabolic steroid — not a peptide
This compound is an anabolic steroid, not a research peptide. It has a different risk profile, legal status, and side-effect spectrum. The information here is for education only and is not medical advice or a recommendation to use. Read the medical disclaimer.
How it's taken (route)
a deeper shot into a muscle, usually the glute, thigh, or shoulder
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- Documented dose
- 200–600 mg
- Typical frequency
- Once per week
- Cycle
- 16 weeks on, 16 off
- Half-life
- Roughly 6-12 days (decanoate ester)
- Common vial sizes
- 250 mg
- Regulatory status
- Controlled anabolic steroid (Schedule III in the US). Prescription only.
Dose on a U-100 syringe
This dose is too large to draw in one standard U-100 insulin syringe at common mixes. It is typically drawn from a larger vial, mixed at a higher concentration, or split into more than one injection. Run your own vial through the reconstitution calculator.
What it does
Nandrolone decanoate builds mass slowly and steadily and is widely reported to ease joint discomfort through improved collagen and fluid retention. It needs long run times (14-16 weeks) to show its value, and it is nearly always run alongside testosterone because it suppresses hard and can cause sexual dysfunction on its own.
Mechanism
19-nortestosterone derivative with strong anabolic and lower androgenic activity. Converts partly to dihydronandrolone rather than DHT, and raises prolactin in some users, which drives the classic libido and erectile issues.
Storage — lyophilisedwhat's this?
Oil solution: room temperature, away from light.
Storage — reconstitutedwhat's this?
Keep the vial clean and use within the labelled shelf life.
Reconstitution noteswhat's this?
Ready to inject in oil. Very long detection window - months, which matters for tested athletes.
Commonly reported side effects
- Sexual dysfunction and low libido (deca dick)
- Raised prolactin
- Strong suppression of natural testosterone, slow recovery
- Water retention
- Mood changes
- Blood pressure increase
Contraindications noted
- Any history of erectile or libido problems
- Prolactin disorders
- Trying to conceive
- Prostate or breast cancer
- Uncontrolled hypertension or heart disease
- Under 21 years of age
- Drug-tested athletes
Research notes
Studied clinically for anemia, osteoporosis and HIV wasting at low doses. Bodybuilding doses are anecdotal. Prolactin, estradiol, lipids and blood pressure should be monitored.
Vendors carrying Nandrolone Decanoate (Deca-Durabolin)
These research suppliers list this compound. Prices, vial sizes and testing vary — always check the current lot certificate before you buy.
Peptide Streak does not sell peptides and is not affiliated with these vendors. Some list metabolic compounds under coded product names.