Nandrolone decanoate is an injectable anabolic steroid. It is nandrolone (19-nortestosterone) with a 10-carbon decanoate ester attached, which makes it release slowly from an oil depot in muscle. Organon sold it as Deca-Durabolin, and the FDA first approved it in 1962. In the US its only labeled use was the anemia of kidney failure. Outside medicine it is widely known as “Deca,” and nandrolone is one of the steroids most often found in doping tests (Kicman, Br J Pharmacol 2008).
No nandrolone decanoate product is marketed in the US today. Every listing in Drugs@FDA is discontinued, and at the holder’s request FDA withdrew approval of the original Deca-Durabolin application in December 2024. Earlier, FDA had formally found that the 200 mg/mL brand product was not taken off the market for safety or effectiveness reasons.
This page summarizes what the US label, the European product information, clinical trials and regulators report. It is for education only and is not medical advice.
| Property | Detail |
|---|---|
| Drug class | Anabolic-androgenic steroid; ester of nandrolone (19-nortestosterone) |
| Brand / approval | Deca-Durabolin (Organon), NDA 013132, approved October 5, 1962; generics under several ANDAs |
| Route | Deep intramuscular injection, gluteal muscle preferred |
| Former US strengths | 50, 100 and 200 mg/mL in oil |
| Former US labeled dose | Anemia of kidney disease: 50–100 mg/week (women), 100–200 mg/week (men), 25–50 mg every 3–4 weeks (children 2–13) |
| Half-life | Release from the injection depot ≈ 6 days (European label); terminal half-life 7–12 days in healthy men |
| Nandrolone content | ≈ 64% of the ester’s weight (100 mg ester ≈ 64 mg nandrolone) |
| US status | No product marketed; Deca-Durabolin NDA withdrawn December 19, 2024; Schedule III controlled substance |
| WADA status | Prohibited at all times (S1.1, anabolic androgenic steroids) |
What it is
Nandrolone is testosterone without the methyl group at carbon 19, which is why it is also called 19-nortestosterone (Kicman 2008). The decanoate ester has the formula C₂₈H₄₄O₃ and a molecular weight of 428.6 g/mol. Nandrolone itself weighs 274.4 g/mol, so about 64% of each milligram of ester is nandrolone (PubChem).
As with testosterone esters, the ester is inactive. It makes the molecule more fat-soluble so it leaves the oil depot slowly, and it is then cut off in the blood to release free nandrolone. The US generic label described 100 mg/mL and 200 mg/mL solutions in sesame oil with benzyl alcohol (US label). The Irish Deca-Durabolin 50 mg/mL product used arachis (peanut) oil (HPRA SmPC).
Why it is less androgenic than testosterone
Testosterone and nandrolone behave differently in tissues that contain the enzyme 5α-reductase, such as the prostate and skin:
| Hormone | Product of 5α-reductase | Effect on androgen-receptor binding |
|---|---|---|
| Testosterone | Dihydrotestosterone (DHT) | Stronger binding: the signal is amplified |
| Nandrolone | Dihydronandrolone (DHN) | Equal or weaker binding: the signal is not amplified |
This was shown in rat tissue binding studies (Tóth and Zakár, J Steroid Biochem 1982). Muscle has little 5α-reductase, so there nandrolone acts in its own right. This is the accepted explanation for nandrolone’s higher muscle-to-androgenic ratio in animal assays (Kicman 2008). Kicman also notes that nandrolone has some progestational activity.
About anabolic:androgenic ratios. Online sources quote exact ratios for nandrolone. Such ratios come from rat assays, and we could not trace the commonly quoted figures to an original source, so we do not repeat them. The more important point is in both the US label and the review literature: complete separation of anabolic from androgenic effects has never been achieved, and long-term use causes virilization in women and children.
Pharmacokinetics
Two human studies define how the drug behaves after injection:
| Parameter | Value | Source |
|---|---|---|
| Release of the ester from the muscle depot | Half-life ≈ 6 days | Wijnand et al. 1985; European label |
| Breakdown of the ester in blood | Half-life of 1 hour or less | Wijnand et al. 1985 |
| Combined hydrolysis, distribution and elimination of nandrolone | Half-life 4.3 h | Wijnand et al. 1985 |
| Peak serum nandrolone, 50 / 100 / 150 mg | 2.14 / 4.26 / 5.16 ng/mL | Bagchus et al. 2005 |
| Time to peak | 30 h (50 and 100 mg); 72 h (150 mg) | Bagchus et al. 2005 |
| Terminal half-life | 7–12 days | Bagchus et al. 2005 |
Free nandrolone is cleared within hours, so the slow release from the depot sets how long a dose lasts. The European label describes a duration of action of about three weeks per injection. Serum levels and total exposure rose in proportion to the dose across 50–150 mg in 54 healthy young men (Bagchus et al., JCEM 2005).
Nandrolone is metabolized in the liver. The main urinary products are 19-norandrosterone (19-NA) and 19-noretiocholanolone (19-NE), and these are the markers used in doping tests.
Approved medical use
United States
The US label approved nandrolone decanoate for one use: managing the anemia of renal insufficiency, where it “has been shown to increase hemoglobin and red cell mass” (US label). Patients who had their kidneys surgically removed were reported to respond less well. The label’s dosing for this use:
| Patient group | Labeled dose |
|---|---|
| Women | 50–100 mg per week |
| Men | 100–200 mg per week |
| Children aged 2–13 | 25–50 mg every 3–4 weeks |
The label told prescribers to stop the drug if the blood count had not improved within six months. It also said therapy should be intermittent where possible, and that adequate iron intake was needed for a full response.
Europe
The Irish product information for Deca-Durabolin 50 mg/mL (2010) covered a broader set of uses (HPRA SmPC):
- conditions with catabolism and negative nitrogen balance, such as debility, burns, osteoporosis, refractory anemia and renal failure;
- as an add-on in disseminated breast cancer in women.
The usual adult dose there was much lower: 25–50 mg once every 3 weeks. For children, the dose was not to exceed 0.5 mg/kg every 3 weeks.
How it left the US market
- 1962. FDA approved Deca-Durabolin (NDA 13-132).
- 1983. FDA’s drug-efficacy review (DESI) found nandrolone decanoate effective for its labeled indications.
- 2002. Organon told FDA it was no longer marketing the 200 mg/mL product.
- 2010. In response to a citizen petition, FDA determined that the 200 mg/mL product “was not withdrawn from sale for reasons of safety or effectiveness,” so generics could still be approved (75 FR 48351).
- December 19, 2024. At the request of the holder, Woodward Specialty, FDA withdrew approval of NDA 013132 (50, 100 and 200 mg/mL), because the products were no longer marketed (89 FR 91410).
All generic nandrolone decanoate listings in Drugs@FDA are also marked discontinued (Drugs@FDA).
What the research shows
Kidney disease: muscle and anemia
The best-known trial randomized 29 dialysis patients to nandrolone decanoate 100 mg or placebo, injected weekly for 6 months (Johansen et al., JAMA 1999). A later 2×2 factorial trial in 79 hemodialysis patients tested weekly nandrolone (100 mg for women, 200 mg for men) and lower-body resistance exercise for 12 weeks (Johansen et al., JASN 2006).
| Outcome | Nandrolone | Comparison |
|---|---|---|
| Lean body mass, 6 months (1999) | +4.5 kg | +1.9 kg on placebo |
| Walk and stair-climb time, 6 months (1999) | 36.5 → 32.7 s | 38.7 → 42.1 s on placebo |
| Grip strength (1999) | No change | No change |
| Lean body mass, 12 weeks (2006) | +3.1 kg | Exercise alone did not raise lean mass |
| Quadriceps cross-sectional area (2006) | Increased | Exercise also increased it; the effects added up |
Strength gains in the 2006 trial came mainly from exercise, and only exercise improved self-reported physical function.
Two systematic reviews summarize the wider evidence:
- A 2014 Cochrane review of 8 small trials (181 participants) found that nandrolone plus erythropoietin raised hematocrit by 2.54% more than erythropoietin alone (95% CI 0.96–4.12). The authors concluded there was “insufficient evidence” that androgens benefit adults with kidney-related anemia (Yang et al., Cochrane 2014).
- A 2026 meta-analysis of 15 randomized trials published between 1974 and 2021 found a lean-mass gain of 2.63 kg (95% CI 1.60–3.65; 4 trials, n = 125). Hemoglobin (+0.81 g/dL) and hematocrit (+3.12%) also favored nandrolone, but certainty was very low and results varied widely between trials (Câmara et al., Endocrine 2026).
HIV-associated weight loss
Several randomized trials tested nandrolone in people with HIV who had lost weight:
| Trial | Participants | Regimen, duration | Main result |
|---|---|---|---|
| Gold et al., HIV Med 2006 | 303 men | Nandrolone 150 mg vs testosterone 250 mg vs placebo, every 2 weeks, 12 weeks | Fat-free mass +1.34 kg vs placebo (95% CI 0.60–2.08) |
| Storer et al., JCEM 2005 | Men with 5–15% weight loss | Nandrolone 150 mg every 2 weeks vs placebo; growth hormone 6 mg/day as open-label reference, 12 weeks | Lean mass +1.6 kg vs +0.4 kg on placebo; growth hormone +2.5 kg (not significantly different from nandrolone) |
| Mulligan et al., Arch Intern Med 2005 | 38 women | Nandrolone 100 mg vs placebo, every other week, 12 weeks | Weight +4.6 kg and lean mass +3.5 kg (significant vs placebo) |
In the Gold trial, nandrolone added 1.00 kg more body weight than testosterone (95% CI 0.27–1.74). The difference in fat-free mass versus testosterone, 0.69 kg, was not statistically significant. In the Storer trial, growth hormone caused more side effects and more dropouts than nandrolone.
Osteoporosis in older women
A two-year double-blind trial randomized 65 women over 70 with osteoporosis to nandrolone decanoate 50 mg or placebo every 3 weeks; all took 500 mg calcium daily (Frisoli et al., J Gerontol 2005):
| Outcome at 2 years | Nandrolone | Placebo |
|---|---|---|
| Lumbar spine BMD vs baseline | +3.7% | — |
| Femoral neck BMD vs baseline | +4.7% | — |
| New vertebral fractures | 21% | 43% |
| Hemoglobin vs baseline | +14.3% | Smaller rise (difference significant) |
BMD is bone mineral density. Femoral neck and trochanter BMD were significantly higher than with placebo, and lean body mass rose by 11.9% over two years.
A 2025 meta-analysis of 7 trials (293 women) rated the fracture reduction and muscle gain as moderate-certainty evidence, and the BMD gain as low certainty. Nandrolone also caused more virilizing side effects, mostly mild: hirsutism, acne and voice changes (Camara et al., Cureus 2025).
Side effects and risks
Label warnings
The US label’s warnings section, printed in capitals, covers three class risks (US label):
- Peliosis hepatis. Blood-filled cysts form in the liver and sometimes the spleen, and can lead to liver failure or bleeding into the abdomen.
- Liver cell tumors. These are mostly benign, but fatal malignant tumors have been reported.
- Blood lipid changes. HDL falls and LDL sometimes rises. The label warns that these changes “may be very marked.”
“Deca is easy on the liver.” This is partly true. Nandrolone is not 17α-alkylated, the chemical change tied to cholestasis and most steroid liver tumors. The European label calls a link between liver tumors and nandrolone esters “highly unlikely but cannot be absolutely excluded.” Peliosis hepatis and abnormal liver function are still listed as side effects, and the US label carried the class warnings above.
Hormonal suppression and fertility
Even one dose shuts down the body’s own testosterone production. In 11 healthy men, a single 150 mg injection suppressed LH and FSH (the pituitary hormones that drive the testes) by day 4. Total testosterone stayed lower throughout the 14-day study (Gårevik et al., Andrologia 2016). The US label lists testicular atrophy, low sperm count (oligospermia), impotence and gynecomastia (male breast growth) as adverse reactions.
Lipids and cardiovascular risk
In the same single-dose study, total cholesterol and apolipoprotein B had risen significantly by day 14. The European label lists hypertension and hyperlipidemia as side effects, and advises great caution in people with heart disease, coronary artery disease or hypertension.
Red blood cells and fluid
Nandrolone raises hemoglobin, which is the reason it was used for anemia. The US label advises checking hemoglobin and hematocrit (the share of blood made up of red cells) for polycythemia, an excess of red cells, in patients on high doses. Edema can occur with or without heart failure, and corticosteroids may add to it.
Virilization in women and effects in children
The label lists the following virilizing effects in women:
- deepening of the voice;
- hirsutism (male-pattern hair growth);
- acne;
- clitoral enlargement;
- menstrual irregularities.
Some of these changes are irreversible even after prompt discontinuation. In children, nandrolone can close the growth plates early and reduce adult height. The label therefore calls for wrist and hand X-rays every six months.
Interactions
- Anticoagulants. Anabolic steroids can increase sensitivity to oral anticoagulants such as warfarin, so the anticoagulant dose may need to be lowered (US label).
- Diabetes medicines. Insulin or oral glucose-lowering doses may need adjustment.
- Drugs that may weaken its effect. Rifampicin, barbiturates, phenytoin, carbamazepine and phenylbutazone may reduce its effect (HPRA SmPC).
- Thyroid tests. It can lower thyroxine-binding globulin and total T4, while free thyroid hormone stays normal.
Who should not use it
The US label lists these contraindications:
- men with breast cancer or known or suspected prostate cancer;
- women with breast cancer and high blood calcium;
- pregnancy (Category X, because it masculinizes the fetus);
- nephrosis or the nephrotic phase of nephritis.
The European product also could not be used by people allergic to peanuts or soya, because it contains arachis oil.
Monitoring
The US label lists these checks during treatment:
| What | Why |
|---|---|
| Hemoglobin and hematocrit | Polycythemia at high doses |
| Serum lipids, including HDL | Lipid changes linked to atherosclerosis |
| Liver function tests | Class liver toxicity |
| Bone age X-ray every 6 months (children) | Early growth-plate closure |
| Urine and serum calcium (women with metastatic breast cancer) | Hypercalcemia |
Legal status and use outside medicine
In the US, nandrolone is named in the federal definition of an anabolic steroid (21 U.S.C. 802(41)). Anabolic steroids, including their esters, are Schedule III controlled substances (21 CFR 1308.13). The US label states that the drug has not been shown to be safe and effective for enhancing athletic performance and should not be used for that purpose. No FDA-approved nandrolone decanoate product is currently marketed in the US.
In sport, nandrolone (19-nortestosterone) is prohibited at all times under S1.1 of the 2026 WADA Prohibited List (WADA). It stays detectable for a long time. After a single 150 mg injection in men presumed never to have used it, 19-NA was still detectable at 6 months in 10 of 12 (Bagchus et al. 2005). The same study found low levels of these metabolites before any dosing in 5 of 37 men (14%), so low levels can occur naturally.
For a faster-acting ester of the same hormone, see NPP (nandrolone phenylpropionate). For the closest testosterone comparison, see testosterone cypionate.
Key takeaways
- A long-acting ester of nandrolone. The decanoate releases from the muscle depot with a half-life of about 6 days, and a dose lasts about three weeks. About 64% of the labeled milligrams is nandrolone.
- Approved in the US only for kidney-related anemia. All US products are now discontinued, and the original Deca-Durabolin approval was withdrawn in 2024 at the holder’s request. In 2010, FDA found the brand had not been pulled for safety or effectiveness reasons.
- Real but modest lean-mass gains in sick patients. Trials in dialysis, HIV wasting and older women with osteoporosis showed gains of roughly 1.3–4.5 kg. Evidence for better strength or function is weaker, and much of the data is decades old.
- Less androgenic, not non-androgenic. 5α-reductase weakens nandrolone instead of strengthening it, but virilization in women still occurs, and some of it is permanent.
- Strong suppression and long detection. A single 150 mg dose suppressed LH, FSH and testosterone in healthy men, and its metabolites can stay detectable for 6 months or more.
Sources
- Watson Laboratories. Nandrolone decanoate injection USP, prescribing information (revised March 2006). DailyMed; Drugs@FDA, NDA 013132.
- Organon. Deca Durabolin 50 mg/ml solution for injection (syringe), summary of product characteristics, PA 0964/008/002, July 2010. HPRA.
- Food and Drug Administration. Determination that DECA-DURABOLIN (nandrolone decanoate) injection, 200 milligrams/milliliter, 1 milliliter, was not withdrawn from sale for reasons of safety or effectiveness. Federal Register. August 10, 2010;75:48351 (FR Doc 2010-19698). Federal Register.
- Food and Drug Administration. Pfizer, Inc., et al.; withdrawal of approval of 26 new drug applications. Federal Register. November 19, 2024;89:91410 (FR Doc 2024-26913). govinfo.
- National Center for Biotechnology Information. Nandrolone decanoate, PubChem CID 9677. PubChem.
- Kicman AT. Pharmacology of anabolic steroids. Br J Pharmacol. 2008;154(3):502–521. PubMed.
- Tóth M, Zakár T. Relative binding affinities of testosterone, 19-nortestosterone and their 5 alpha-reduced derivatives to the androgen receptor and to other androgen-binding proteins: a suggested role of 5 alpha-reductive steroid metabolism in the dissociation of “myotropic” and “androgenic” activities of 19-nortestosterone. J Steroid Biochem. 1982;17(6):653–660. PubMed.
- Wijnand HP, Bosch AM, Donker CW. Pharmacokinetic parameters of nandrolone (19-nortestosterone) after intramuscular administration of nandrolone decanoate (Deca-Durabolin) to healthy volunteers. Acta Endocrinol Suppl (Copenh). 1985;271:19–30. PubMed.
- Bagchus WM, Smeets JM, Verheul HA, et al. Pharmacokinetic evaluation of three different intramuscular doses of nandrolone decanoate: analysis of serum and urine samples in healthy men. J Clin Endocrinol Metab. 2005;90(5):2624–2630. PubMed.
- Johansen KL, Mulligan K, Schambelan M. Anabolic effects of nandrolone decanoate in patients receiving dialysis: a randomized controlled trial. JAMA. 1999;281(14):1275–1281. PubMed.
- Johansen KL, Painter PL, Sakkas GK, et al. Effects of resistance exercise training and nandrolone decanoate on body composition and muscle function among patients who receive hemodialysis: a randomized, controlled trial. J Am Soc Nephrol. 2006;17(8):2307–2314. PubMed.
- Yang Q, Abudou M, Xie XS, Wu T. Androgens for the anaemia of chronic kidney disease in adults. Cochrane Database Syst Rev. 2014;(10):CD006881. PubMed.
- Câmara LC, da Costa Viana DP, de Sousa Monte Alto L, et al. Effects of nandrolone decanoate on lean body mass and anemia in adults with chronic kidney disease: a systematic review and meta-analysis. Endocrine. 2026;91(1):294. PubMed.
- Gold J, Batterham MJ, Rekers H, et al. Effects of nandrolone decanoate compared with placebo or testosterone on HIV-associated wasting. HIV Med. 2006;7(3):146–155. PubMed.
- Storer TW, Woodhouse LJ, Sattler F, et al. A randomized, placebo-controlled trial of nandrolone decanoate in human immunodeficiency virus-infected men with mild to moderate weight loss with recombinant human growth hormone as active reference treatment. J Clin Endocrinol Metab. 2005;90(8):4474–4482. PubMed.
- Mulligan K, Zackin R, Clark RA, et al. Effect of nandrolone decanoate therapy on weight and lean body mass in HIV-infected women with weight loss: a randomized, double-blind, placebo-controlled, multicenter trial. Arch Intern Med. 2005;165(5):578–585. PubMed.
- Frisoli A Jr, Chaves PH, Pinheiro MM, Szejnfeld VL. The effect of nandrolone decanoate on bone mineral density, muscle mass, and hemoglobin levels in elderly women with osteoporosis: a double-blind, randomized, placebo-controlled clinical trial. J Gerontol A Biol Sci Med Sci. 2005;60(5):648–653. PubMed.
- Camara LC, Ferreira MH, Junior NC. Nandrolone decanoate for postmenopausal osteoporosis: a systematic review and meta-analysis of randomized trials. Cureus. 2025;17(11):e98114. PubMed.
- Gårevik N, Börjesson A, Choong E, et al. Impact of single-dose nandrolone decanoate on gonadotropins, blood lipids and HMG CoA reductase in healthy men. Andrologia. 2016;48(5):595–600. PubMed.
- World Anti-Doping Agency. The 2026 Prohibited List (effective January 1, 2026). WADA.
- 21 U.S.C. § 802(41), definition of anabolic steroid; 21 CFR § 1308.13(f), Schedule III anabolic steroids. LII; eCFR.