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injectableanabolic

Norclostebol

4-Chloro-19-nortestosteroneAnabol 4-19
63
Anabolic Ratio
12
Androgenic Ratio
5d
Half-Life

4-chlorinated 19-nortestosterone derivative combining the aromatization blockade of clostebol with the reduced androgenicity of 19-nor compounds. Very mild compound with extremely low androgenic activity. Used medically in France and some European countries for anemia. Very limited modern data.

Mechanism of Action

4-chloro group prevents aromatization. 19-nor structure minimizes 5α-reductive androgenicity. Direct weak AR agonist. Low SHBG binding. Due to extremely low androgenic activity, very little virilization risk even in women — historically used in female patients.

Norclostebol molecule
Molecular structure

Typical Dosing

50 mg
low / week
100 mg
moderate / week
200 mg
high / week

⚠ Warning Flags

  • Extremely rare — virtually unavailable on any market

Effect Profile

Muscle Protein Synthesis
3Low
Nitrogen Retention
3Low
Strength Gains
3Low
Red Blood Cell Production
4Low
Fat Loss
2Minimal
Glycogen Storage
3Low
Recovery Speed
3Low
Collagen Synthesis
3Low

Side Effect Profile

Hormonal Suppression
4Low
Estrogenic Effects
1Minimal
Androgenic Effects
1Minimal
Cardiovascular Strain
2Minimal
Liver Stress
1Minimal
Insulin Resistance
1Minimal
Mood Changes
2Minimal
Prostate Risk
1Minimal

Research Studies

Anabolic and androgenic dissociation: 4-chloro-19-nortestosterone derivatives

Potts GO, et al. · 1975

PubMed

Animal bioassay data establishing norclostebol's unusually favorable anabolic:androgenic separation; levator ani:ventral prostate ratio > 5:1 suggesting excellent anabolic selectivity.