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Nan4.5
Nandrolone (Deca-Durabolin) Research
Mostly mechanism / observationalLimited safety
8 peer-reviewed studies
What the evidence says
Mostly mechanism / observational
Most Nandrolone (Deca-Durabolin) studies are mechanism or observational rather than RCTs that measure a clinical effect — keep findings provisional.
Most evidence is from medium-quality randomised trials published 1999–2025 with a typical study size of 30 participants.
Based on 8 studies · 5 RCTs · 468 total participants
Confidence
Moderate
By outcome
Lean mass & muscle wasting
Mostly mechanism / observational5 studies
Kidney & dialysis
Mostly mechanism / observational4 studies
Hormones & sexual function
Mostly mechanism / observational3 studies
Safety profile
Mostly mechanism / observational3 studies
Anemia & hematology
Too few graded studies2 studies
Heart & blood pressure
Too few graded studies2 studies
Cholesterol & lipids
Too few graded studies1 study
Steady research
2 studies in the last 5 years
199920122025
1RCT2005
Nandrolone administration was associated with a greater increase in LBM (+1.6 +/- 0.3 kg) ... than placebo (+0.4 +/- 0.3 kg; P < 0.05); however, the change in LBM with nandrolone was not significantly different from rhGH ... nandrolone is superior to placebo and not significantly different from a Food and Drug Administration-approved regimen of rhGH in improving lean body mass.
Storer TW, Woodhouse LJ, Sattler F, Singh AB, Schroeder ET, Beck K, Padero M, Mac P, Yarasheski KE, Geurts P, Willemsen A, Harms MK, Bhasin S. · The Journal of clinical endocrinology and metabolism (2005)
Placebo-controlled, double-blind 12-week RCT in HIV-infected men with 5-15% weight loss — nandrolone decanoate 150 mg intramuscularly biweekly vs placebo, with open-label FDA-approved recombinant growth hormone as an active reference
Nandrolone increased lean body mass (by DXA) significantly more than placebo, and the gain was not significantly different from the approved growth-hormone regimen
Also produced greater gains in fat-free mass, body cell mass and intracellular water than placebo, and was better tolerated than rhGH (fewer drug-related adverse effects/discontinuations)
Treatment with nandrolone resulted in significantly greater increases in fat-free mass ... and in weight ... compared with placebo. The mean increase in weight with nandrolone of 1.00 kg ... when compared with testosterone was significant.
Gold J, Batterham MJ, Rekers H, Harms MK, Geurts TB, Helmyr PM, Silva de Mendonça J, Falleiros Carvalho LH, Panos G, Pinchera A, Aiuti F, Lee C, Horban A, Gatell J, Phanuphak P, Prasithsirikul W, Gazzard B, Bloch M, Danner SA; E-1696 Study Investigators. · HIV medicine (2006)
Large multicentre, randomized, double-blind, placebo-controlled trial in 303 HIV-positive men with weight loss or low BMI/body-cell-mass — nandrolone decanoate 150 mg vs testosterone 250 mg vs placebo intramuscularly every 2 weeks for 12 weeks
Nandrolone significantly increased fat-free mass and weight versus placebo, and increased weight significantly more than testosterone
Patient perception of benefit was significantly greater with nandrolone than with both placebo and testosterone
Lean body mass increased significantly in patients given nandrolone compared with patients given placebo ... Treatment with nandrolone for 6 months resulted in a significant increase in LBM associated with functional improvement in patients undergoing dialysis.
Johansen KL, Mulligan K, Schambelan M. · JAMA (1999)
Randomized, double-blind, placebo-controlled trial in 29 dialysis patients — nandrolone decanoate 100 mg vs placebo intramuscularly once weekly for 6 months
Lean body mass increased significantly more with nandrolone than placebo, with a rise in serum creatinine consistent with increased muscle mass
Walking and stair-climbing time improved with nandrolone while it worsened on placebo — a functional, not just compositional, benefit
Patients who received nandrolone decanoate increased their LBM by 3.1 +/- 2.2 kg (P < 0.0001) ... Quadriceps muscle cross-sectional area increased in patients who were assigned to exercise (P = 0.01) and to nandrolone (P < 0.0001) in an additive manner.
Johansen KL, Painter PL, Sakkas GK, Gordon P, Doyle J, Shubert T. · Journal of the American Society of Nephrology : JASN (2006)
Randomized 2x2 factorial trial of nandrolone and resistance exercise in 79 maintenance-hemodialysis patients — weekly nandrolone decanoate (100 mg women / 200 mg men) or placebo, with or without 12 weeks of intradialytic lower-extremity resistance training
Nandrolone increased lean body mass and quadriceps cross-sectional area; exercise added to the cross-sectional-area effect and improved self-reported physical functioning and strength
Demonstrates nandrolone and resistance exercise produce additive anabolic effects in dialysis-related muscle wasting
Hemoglobin and hematocrit experienced similar increases in both groups ... Androgens therapy improved the anemia in elderly male CAPD patients in a similar manner to that observed with rHuEPO.
Navarro JF, Mora C, Macía M, García J. · Kidney international (2002)
Randomized prospective trial in 27 elderly male CAPD (peritoneal dialysis) patients — nandrolone decanoate 200 mg/week intramuscularly vs recombinant human erythropoietin for 6 months for anemia
Hemoglobin and hematocrit rose comparably in both groups; nandrolone also improved nutritional anthropometric and biochemical parameters (weight, BMI, albumin, prealbumin, transferrin)
Outcome anchor for nandrolone's historic FDA-approved anemia-of-CKD indication, grounded in a randomized comparison against the modern standard (erythropoietin)
Pharmacological doses of nandrolone decanoate yielded significant gains in total weight, lean body mass, body cell mass, muscle size, and strength. The increases in lean body mass and muscular strength were significantly augmented with PRT.
Sattler FR, Jaque SV, Schroeder ET, Olson C, Dube MP, Martinez C, Briggs W, Horton R, Azen S. · The Journal of clinical endocrinology and metabolism (1999)
Open-label randomized study in 30 HIV-positive men with <400 CD4 cells — weekly nandrolone alone vs nandrolone plus supervised progressive resistance training (PRT) for 12 weeks
Nandrolone produced significant gains in weight, lean body mass, body cell mass, MRI muscle cross-sectional area and strength; PRT significantly augmented the lean-mass and strength gains
Adds muscle-size (MRI) and strength endpoints to the HIV-wasting evidence and shows the anabolic effect compounds with resistance training
The negative impact of androgens on cardiovascular parameters, such as blood pressure, hematocrit and lipid metabolism, as well as cardiac structure and function, seems to be the mechanism for premature atherosclerosis and cardiomyopathy, respectively, in long-term users.
Smit DL, Bond P, de Ronde W. · Current opinion in endocrinology, diabetes, and obesity (2022)
Mandatory class-level counter-evidence: a review of the prospective HAARLEM cohort of male amateur athletes using anabolic-androgenic steroids (nandrolone among them) — higher-quality than the case-series literature that dominated the field
All users experienced both benefit (strength) and harm (acne, gynecomastia); effects were generally reversible and acute life-threatening toxicity rare, with a distinct but limited impact on liver and kidney function
Gonadal function was disrupted but usually recovered after cessation, while the adverse impact on blood pressure, hematocrit and lipids (lowered HDL) plus cardiac structural/functional change underlies premature atherosclerosis and cardiomyopathy in long-term users
While most individuals recover HPGA function following androgen cessation, a subset experiences prolonged hypogonadism, with symptoms persisting for months or even years ... We propose the term 'Prolonged Post-Androgen Abuse Hypogonadism' (PPAAH).
van Os J, Smit DL, Bond P, de Ronde W. · Frontiers in endocrinology (2025)
Counter-evidence on nandrolone's signature harm: a framework paper on prolonged hypogonadism after anabolic-steroid use — the endocrine basis of the loss of libido and erectile dysfunction users colloquially call 'deca dick'
Androgen use inevitably suppresses the hypothalamic-pituitary-gonadal axis; while most recover after stopping, a subset has persistent hypogonadism lasting months to years
Proposes 'Prolonged Post-Androgen Abuse Hypogonadism' (PPAAH) — persistent hypogonadism six months after cessation with cumulative exposure of at least 150 mg/week for at least six months