Pregnenolone (Wettable) Powder for Compounding (API) (Rx)Pregnenolone powder is a synthetic version of the naturally occurring hormone pregnenolone. It is used in compounding medications as an active pharmaceutical ingredient (API) due to its ability to be formulated into different dosage forms, such as capsules, creams, gels, and injectables. Ships in 2 4 business days. What does Progesterone (Wettable) Mean? Progesterone USP is a white or creamy white, crystalline powder. It is stable in air. Wettable