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The present study aimed to develop polyethylene glycol–liquid crystals (PEG-LC) ointment formulations, assess their formulation characteristics, and establish their biocompatibility and impact on transdermal drug administration. PEG-LC formulations were prepared using a hydrophilic molecule, p-aminobenzoic acid (PAB). Formulation characterizations such as small-angle X-ray scattering, viscosity, pH, zeta potential, and the particle sizes of the formulations were examined to determine the physicochemical properties of the prepared formulations. The drug release profile of PEG-LC ointment formulations was assessed with a dialysis membrane. In vitro skin permeation testing was performed to establish whether the PEG-LC formulations improved drug skin penetration. The MTT and comet assays were performed to assess the biocompatibility of the formulations. Our data showed that the method is effective in forming hexosome-type PEG-LC formulations and that they were biocompatible. Furthermore, the PEG-LC formulations significantly improved PAB skin penetration when compared with commercial PEG. The PEG-LC formulation is a promising carrier for the delivery of hydrophilic drugs.