Nandrolone Decanoate vs Testosterone Undecanoate
A side-by-side research comparison of Nandrolone Decanoate and Testosterone Undecanoate across mechanism, dosing, half-life, benefits, side effects and research status.
Comparison table
| Attribute | Nandrolone Decanoate | Testosterone Undecanoate |
|---|---|---|
| Full name | Nandrolone Decanoate (Deca-Durabolin) | Testosterone Undecanoate (Ultra-Long Ester) |
| Category | Anabolic Steroids | Anabolic Steroids |
| Status | Prescription drug (controlled substance) | FDA-approved drug (controlled substance) |
| Mechanism | Nandrolone is testosterone lacking the 19-carbon methyl group, giving it high anabolic and lower androgenic activity. It binds androgen receptors and, unlike testosterone, converts to a weaker androgen (rather than DHT) in some tissues, reducing certain androgenic effects but not estrogen-related ones. | The large undecanoate ester dramatically slows release, giving weeks-long duration from a single injection. Oral undecanoate is absorbed via the lymphatic system, partly bypassing first-pass liver metabolism. |
| Molecular weight | 428.6 Da | 456.7 Da |
| Half-life | ~6-12 days | ~20-34 days (injection depot) |
| Bioavailability | Intramuscular injection | Deep IM injection or oral (lymphatic absorption) |
| Typical dose | Medical: ~50-100 mg every 1-4 weeks | Injection every ~10-14 weeks (medical); oral 2x daily with food |
| Frequency | Weekly to monthly (medical) | Infrequent (injection) or twice daily (oral) |
| Route | Intramuscular injection | Deep intramuscular injection or oral |
Nandrolone Decanoate reported benefits
- Lean muscle mass gains
- Reputed joint comfort
- Increased red blood cell production
- Treats certain anemias/wasting (medical)
- Improved nitrogen retention
Testosterone Undecanoate reported benefits
- Very infrequent injections (convenience)
- Stable long-term testosterone (medical)
- Oral option avoids most liver toxicity
- Restores testosterone in deficiency
Related comparisons
Research and educational reference only. Not medical advice.