PT - JOURNAL ARTICLE AU - Charles F. Minto AU - Christopher Howe AU - Susan Wishart AU - Ann J. Conway AU - David J. Handelsman TI - Pharmacokinetics and Pharmacodynamics of Nandrolone Esters in Oil Vehicle: Effects of Ester, Injection Site and Injection Volume DP - 1997 Apr 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 93--102 VI - 281 IP - 1 4099 - http://jpet.aspetjournals.org/content/281/1/93.short 4100 - http://jpet.aspetjournals.org/content/281/1/93.full SO - J Pharmacol Exp Ther1997 Apr 01; 281 AB - We studied healthy men who underwent blood sampling for plasma nandrolone, testosterone and inhibin measurements before and for 32 days after a single i.m. injection of 100 mg of nandrolone ester in arachis oil. Twenty-three men were randomized into groups receiving nandrolone phenylpropionate (group 1, n = 7) or nandrolone decanoate (group 2, n = 6) injected into the gluteal muscle in 4 ml of arachis oil vehicle or nandrolone decanoate in 1 ml of arachis oil vehicle injected into either the gluteal (group 3, n = 5) or deltoid (group 4,n = 5) muscles. Plasma nandrolone, testosterone and inhibin concentrations were analyzed by a mixed-effects indirect response model. Plasma nandrolone concentrations were influenced (P < .001) by different esters and injection sites, with higher and earlier peaks with the phenylpropionate ester, compared with the decanoate ester. After nandrolone decanoate injection, the highest bioavailability and peak nandrolone levels were observed with the 1-ml gluteal injection. Plasma testosterone concentrations were also influenced (P < .001) by the ester and injection site, with the most rapid, but briefest, suppression being due to the phenylpropionate ester, whereas the most sustained suppression was achieved with the 1-ml gluteal injection. Plasma inhibin concentrations were also significantly influenced by injection volume and site, with the lowest nadir occurring after the nandrolone decanoate 1-ml gluteal injection. Thus, the bioavailability and physiological effects of a nandrolone ester in an oil vehicle are greatest when the ester is injected in a small (1 ml vs. 4 ml) volume and into the glutealvs. deltoid muscle. We conclude that the side-chain ester and the injection site and volume influence the pharmacokinetics and pharmacodynamics of nandrolone esters in an oil vehicle in men. The American Society for Pharmacology and Experimental Therapeutics