Proteins and peptides are essential biomacromolecules that play a number of physiological and biological roles in the body. These macromolecules are thought to provide attractive platforms for the delivery of medications and genes because they are biocompatible and biodegradable. However, peptides and proteins have significant drawbacks that hinder their efficient transport, including as enzymatic breakdown, brief circulation half-lives, and poor membrane permeability. In addition to measures for improving bioavailability and lipid nanocarriers as potential systems for peptide and protein medication delivery, this article briefly examines the inherent difficulties in peptide and protein distribution.