Provided are high concentration compositions of tissue kallikrein-1 (KLK1) and methods of parenterally administering such compositions to a subject in need thereof, where absorption into the circulation via, for example, intravenous or subcutaneous administration improves systemic pharmacokinetics, bioavailability, safety, and/or convenience relative to intravenous or other forms of administration. Also provided are recombinant human KLK1 (rhKLK1) polypeptides that can be readily concentrated to high protein concentrations, and substantially pure compositions thereof.