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injectableanabolic

Nandrolone Decanoate

DecaDeca-DurabolinNPP (short ester)
125
Anabolic Ratio
37
Androgenic Ratio
15d
Half-Life

One of the most studied synthetic AAS. Highly anabolic, low androgenic. Excellent for joint health and lean mass. Very suppressive. Famous 'Deca Dick' risk from prolactin/progestin activity.

Mechanism of Action

Binds AR with high affinity. 5α-reduces to dihydronandrolone (much weaker than DHT, minimizing androgenic scalp/skin effects). Does NOT aromatize significantly but has progestogenic activity — raises prolactin, suppresses LH/FSH more potently than testosterone.

Nandrolone Decanoate molecule
Molecular structure

Typical Dosing

200 mg
low / week
400 mg
moderate / week
600 mg
high / week

⚠ Warning Flags

  • High prolactin risk — use cabergoline on-cycle
  • Very long clearance time (up to 18 months detectable)
  • 'Deca Dick' (sexual dysfunction) risk if not paired with sufficient testosterone

Effect Profile

Muscle Protein Synthesis
7High
Nitrogen Retention
8Very High
Strength Gains
6Moderate
Red Blood Cell Production
6Moderate
Fat Loss
3Low
Glycogen Storage
6Moderate
Recovery Speed
8Very High
Collagen Synthesis
8Very High

Side Effect Profile

Hormonal Suppression
8Very High
Estrogenic Effects
3Low
Androgenic Effects
3Low
Cardiovascular Strain
4Low
Liver Stress
1Minimal
Insulin Resistance
2Minimal
Mood Changes
5Moderate
Prostate Risk
2Minimal

Research Studies

The effect of nandrolone decanoate on bone mineral density, muscle mass, and hemoglobin levels in elderly women with osteoporosis

Frisoli A Jr, et al. · 2005

PubMed

Nandrolone decanoate significantly increased bone density and lean mass in elderly women, demonstrating potent anabolic effects with minimal androgenic side effects.

Anabolic effects of nandrolone decanoate in patients receiving dialysis

Johansen KL, et al. · 1999

PubMed

Dialysis patients receiving nandrolone showed significant increases in lean body mass and muscle strength, validating its anti-catabolic and anabolic properties.

Anabolic effects of low dose nandrolone decanoate in HIV-positive men

Brodsky IG, et al. · 1996

PubMed

Low-dose nandrolone significantly improved nitrogen retention and lean mass in HIV+ patients, confirming its potent anabolic-to-androgenic ratio advantage.