Nandrolone Phenylpropionate is one of the esters of Nandrolone. NPP (also known as Durabolin) has a strong anabolic effect. This drug stimulates protein synthesis and promotes protein accumulation in muscle cells. Nandrolone Phenylpropionate is very similar to Nandrolone Decanoate. The difference is in the details: Decanoate should be used only once a week. Nandrolone Phenylpropionate is quickly absorbed into the blood (in comparison with Nandrolone Decanoate). NPP is effectively used as a doping agent for muscle growth and overall strength.