While Deca-Durabolin is the most commonly used Nandrolone based steroid it is far from the only one and in recent years the popular Nandrolone-Phenylpropionate has increased in popularity; commonly referred to as NPP and often found under the trade name Durabolin. In many ways NPP is very similar to the original Decanoate version; meaning, the nature of the hormones is for all intense purposes the same with either form. However, when examining the two compounds we have two distinct esters, one with the Decanoate ester while NPP is a Phenylpropionate ester based form. As each one carries its own ester NPP will become active in a noticeable way much faster but its total lasting effect is very short lived compared to the large ester based Nandrolone. Further, because Phenylpropionate is a smaller ester the total mass of the compound will yield more Nandrolone on a per milligram basis. At first glance this would seem to lend to NPP being slightly superior as it becomes active much faster but this isn’t necessarily true; while it will activate much faster, fast is not always beneficial, especially when we consider solidifying gains. However, in the long and short both compounds are very similar but some have said to report less water retention with the NPP form and this is common with smaller ester based steroids.
Nevertheless, real life experiences often show that the original may indeed be slightly more powerful; remember, real life and what’s on paper do not always matchup hand in hand and in the end you will have to find what works best for you.
Heavy consumption of the essential amino acid lysine (as indicated in the treatment of cold sores) has allegedly shown false positives in some and was cited by American shotputter C. J. Hunter as the reason for his positive test, though in 2004 he admitted to a federal grand jury that he had injected nandrolone.  A possible cause of incorrect urine test results is the presence of metabolites from other AAS, though modern urinalysis can usually determine the exact steroid used by analyzing the ratio of the two remaining nandrolone metabolites. As a result of the numerous overturned verdicts, the testing procedure was reviewed by UK Sport . On October 5, 2007, three-time Olympic gold medalist for track and field Marion Jones admitted to use of the drug, and was sentenced to six months in jail for lying to a federal grand jury in 2000.