Primtoro 100 ™ is a Class I steroid working well at the androgen receptor but which apparently is ineffective in non-AR-mediated anabolic effects. It is most closely compared to nandrolone, requiring a little higher dosage to achieve the same anabolic effect, but since it is pleasant to use at doses considerably higher than what is pleasant for nandrolone esters, it can achieve higher maximal effectiveness. 400 mg/week should be considered a reasonable minimum dose. It appears to cause less inhibition than nandrolone or testosterone for any given degree of anabolic effect, perhaps because of low CNS activity, lack of conversion to DHT, and lack of aromatization to estrogen. Unlike nandrolone, it is not metabolically deactivated by 5a-reductase and therefore is not as kind to the skin and hair as that drug. However, when used by itself at modest doses, by suppressing natural testosterone and DHT production, it can improve skin relative to using no anabolic steroids at all.