Nandrolone Decanoate
Nortestosterone decanoate
Also known as: Deca-Durabolin · Nortestosterone decanoate · Nortestosterone decylate
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Adjunctive treatment of chronic idiopathic myelofibrosis | 2 mg/kg IM weekly | IM | weekly | 3 weeks | 🌎 NA |
| Disuse muscle atrophy secondary to immobilization | 1.5 mg/kg IM once weekly | IM | once weekly | up to 8 weeks | 🌎 NA |
| Treatment of anemia in patients with chronic renal failure | 1-1.5 mg/kg IM once weekly | IM | once weekly | May require 2-3 months to achieve beneficial effects | 🌎 NA |
| Treatment of anemia in patients with chronic renal failure | 5 mg/kg IM (maximum of 200 mg/week) every 2-3 weeks | IM | every 2-3 weeks | — | 🌎 NA |
| Treatment of metabolic and endocrine anemias | 5 mg/kg IM once weekly | IM | once weekly | — | 🌎 NA |
| Aplastic anemia | 1-3 mg/kg IM weekly | IM | weekly | — | 🌎 NA |
| Appetite stimulant | 5 mg/kg IM weekly | IM | weekly | — | 🌎 NA |
- Adjunctive treatment of chronic idiopathic myelofibrosis: Used with prednisolone (2-3 mg/kg PO once daily for 3-4 weeks, then tapered). If anemia does not respond, azathioprine may be added.
- Disuse muscle atrophy secondary to immobilization: Start from the day of surgery/immobilization.
- Treatment of anemia in patients with chronic renal failure: Evidence to support use is poor.
- Treatment of metabolic and endocrine anemias: Maximum of 200 mg. Most resolve with correction of underlying disease process.
- Appetite stimulant: Maximum 200 mg/week.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| FeLV-induced anemia or as a general bone marrow stimulant | 10-20 mg IM once weekly | IM | once weekly | — | 🌎 NA |
| Chronic anemia secondary to feline cardiomyopathy | 50 mg IM weekly | IM | weekly | — | 🌎 NA |
- FeLV-induced anemia or as a general bone marrow stimulant: Is of questionable benefit.
Reptiles
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| To reduce protein catabolism in renal disease of lizard species | 1 mg/kg IM every 7-28 days | IM | every 7-28 days | — | 🌎 NA |
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Nandrolone decanoate is an injectable anabolic steroid historically used in veterinary medicine to stimulate erythropoiesis in patients with certain anemias (e.g., secondary to chronic renal failure or aplastic anemias) and as an appetite stimulant.
- Clinical Shift: Anabolic steroids are rarely recommended or used today in veterinary medicine due to the availability of safer and more targeted therapies (e.g., recombinant human erythropoietin/darbepoetin for anemia, and mirtazapine or capromorelin for appetite stimulation).
- Regulatory Status: It is a C-III Controlled Substance due to the high potential for human abuse.
- Availability: There are currently no FDA-approved commercial products marketed in the USA for veterinary or human use; it may only be available through compounding pharmacies.
Mechanism of action
Nandrolone is a synthetic derivative of testosterone with enhanced anabolic and reduced androgenic properties.
- Anabolic Effects: Binds to intracellular androgen receptors (AR) → translocates to the nucleus → alters gene transcription. In the presence of adequate protein and calories, it promotes body tissue-building processes and reverses catabolism.
- Erythropoiesis Stimulation: Enhances red blood cell counts by directly stimulating red cell precursors in the bone marrow, increasing red cell 2,3-diphosphoglycerate (2,3-DPG), and stimulating erythropoietin (EPO) production in the kidneys.
- Endocrine Feedback: Suppresses endogenous testosterone release by inhibiting luteinizing hormone (LH). Large doses impede spermatogenesis via negative feedback inhibition of follicle-stimulating hormone (FSH).
- Metabolic Effects: Causes retention of nitrogen, sodium, potassium, and phosphorus, and decreases urinary excretion of calcium.
Safety & warnings
Contraindications
- Hepatic dysfunction
- Hypercalcemia
- History of myocardial infarction
- Pituitary insufficiency
- Prostate carcinoma
- Mammary carcinoma
- Benign prostatic hypertrophy (BPH)
- Nephrotic stage of nephritis
- Pregnancy (FDA Category X - known teratogen)
Adverse effects
- Sodium, calcium, potassium, water, chloride, and phosphate retention
- Hepatotoxicity
- Behavioral changes (androgenic effects, e.g., increased aggression)
- Reproductive abnormalities (oligospermia, estrus suppression)
- Masculinization of female fetuses (teratogenic)
Precautions
Pregnancy Warning: FDA Category X. Anabolic steroids can cause masculinization of the fetus. The risk of use in pregnant animals clearly outweighs any possible benefit.
- Nursing Mothers: It is unknown if anabolic steroids are excreted in maternal milk. Due to the potential for serious adverse reactions in nursing offspring, a decision should be made to either discontinue nursing or discontinue the drug.
- Laboratory Alterations: Can decrease protein-bound iodine (PBI), thyroxine-binding globulin, and total T4 concentrations while increasing resin uptake of T3 and T4 (free thyroid hormones remain unaltered). Can decrease creatinine and creatine excretion, increase 17-ketosteroid excretion, alter blood glucose, suppress clotting factors (II, V, VII, X), and elevate liver enzymes (AST, ALT, ALP, bilirubin).
Drug interactions
Anabolic agents may potentiate the effects of anticoagulants; monitoring of INR and dosage adjustment of the anticoagulant are recommended.
Anabolics may enhance the edema that can be associated with ACTH or adrenal steroid therapy.
Anabolics may decrease blood glucose and decrease insulin requirements; diabetic patients may need dosage adjustments.
Monitoring
- Androgenic side effects (behavioral changes)
- Fluid and electrolyte status (especially sodium, potassium, calcium)
- Liver function tests (AST, ALT, ALP, bilirubin)
- Red blood cell count and indices
- Weight and appetite
Pharmacokinetics
Absorption
Administered via deep intramuscular injection. The decanoate ester provides a slow release from the injection site.
Distribution
No specific veterinary information located.
Metabolism
Metabolized in the liver.
Elimination
No specific veterinary information located.
Overdose
No specific information was located for this agent in veterinary species. In humans, sodium and water retention can occur after overdosage of anabolic steroids.
- Treatment: Treat supportively. Monitor liver function and electrolyte status should an inadvertent overdose be administered.
Available products
Formulations
- Injectable solution (compounded, typically in sesame oil)
Veterinary
- None commercially available in the USA. Potentially available from compounding pharmacies.
Human-labeled
- None commercially available in the USA.
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store at temperatures less than 40°C, preferably between 15-30°C (59-86°F). Protect from freezing and light.
Client information
- Controlled Substance: Because of the potential for abuse of anabolic steroids by humans, this agent is a controlled (C-III) drug. It must be kept in a secure area and strictly out of the reach of children.
- Behavioral Changes: Watch your pet for any signs of increased aggression or other behavioral changes, which can be a side effect of steroid hormones.
- Physical Monitoring: Monitor your pet for signs of fluid retention (swelling) or jaundice (yellowing of the eyes/gums), which could indicate liver stress.
- Follow-up: Regular veterinary visits and blood tests are required to monitor your pet's red blood cell count and liver function while on this medication.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.