The crystal structure of p-synephrine was solved from a high-resolution X-ray powder diffraction pattern optimized by energy-minimization calculations using the Dreiding force field. The title compound crystallizes in a monoclinic system (space group P2(1)/c, Z=4, with a = 8.8504(11) angstrom, b=12.1166(15) angstrom, c = 9.7820(11) angstrom, beta = 122.551(2), V=884.21(19) angstrom(3) and d=1.256 g cm(-3)). Since p-synephrine degrades upon melting, its melting data were determined from DSC experiments carried out as a function of the heating rate. This method allowed determining a melting temperature and enthalpy equal to 199.8 +/- 1.3 degrees C and 57 +/- 3 kJ mol(-1), respectively. (C) 2016 Elsevier B.V. All rights reserved.