Pharmacodynamics and Toxicity of Nandrolone decanoate

Nandrolone decanoate, or nandrolone 17β-decanoate, is a synthetic estrane steroid and a derivative of testosterone. It is an androgen ester; specifically, it is the C17β decylate (decanoate) ester of nandrolone (19-nortestosterone), which itself is the 19-demethylated analogue of testosterone.

Effects

nandrolone decanoate is considered to have strong anabolic effects but weak androgenic effects (potency ratios of 3.29–4.92 and 0.31–0.41). In particular, nandrolone esters are thought to have the highest ratio of anabolic to androgenic effects of any AAS. The low androgenicity of nandrolone decanoate is thought to be due to the fact that nandrolone is inactivated by 5α-reductase via transformation into the low-affinity androgen receptor (AR) ligand 5α-dihydronandrolone. This is thought to result in a lower incidence and magnitude of side effects.

Pharmacodynamics

Nandrolone decanoate is an alkylated anabolic steroid indicated in the management of anemia of renal insufficiency and as an adjunct therapy in the treatment of senile and postmenopausal osteoporosis.It has a long duration of action as it is given every 3-4 weeks, and a wide therapeutic window as acute overdoses are rare.Patients should be counselled regarding the risks of giving this drug to patients with cardiac, renal, or hepatic diseases.

Mechanism of action

Nandrolone decanoate is hydrolyzed to nandrolone, possibly by PDE7B.Nandrolone is brought into cells by receptor mediated endocytosis, where it interacts with the androgen receptor.After binding to the androgen receptor, a conformational change occurs, the androgen receptor enters the nucleus, dimerizes, and can then bind to segments of DNA to regulate transcription.Androgens can also regulate transcription through activation of ERK, Akt, and MAPK; or binding to and competitively inhibiting transcription factors.

Toxicity

Data regarding acute overdose of nandrolone decanoate are not readily available.However, patients experiencing a chronic overdose of anabolic steroids may experience adverse effects including suppression of testosterone and spermatogenesis, shrinking of testicles, decreased libido, and erectile dysfunction in men; and suppressed estrogen, progesterone, and ovulation, amenorrhea, and clitoromegaly in women.Patients may also experience neuropsychiatric, cardiovascular, and hepatic adverse effects.Alkylated anabolic steroids such as nandrolone decanoate are more likely to cause hepatic adverse effects.Treat patients with symptomatic and supportive measures.