DSIP for Deep Sleep: Benefits, Dosage & Safety Frontiers Pichia pastoris secreted peptides crossing the blood brain barrier and DSIP fusion peptide efficacy in PCPA induced insomnia mouse models Still injecting in the same spot every time? Read this. Where you inject your peptides can actually affect absorption, comfort, and results. Quick guide: Abdomen: fastest absorption Upper arms Subcutaneous Injection Sites and Instructions for Safe Self Administration