Glassy states of nine acetaminophen-nifedipine compositions have been made by slowly supercooling their melts, and calorimetric T g and the nonexponential, nonlinear relaxation parameters b and x that are used in modeling the mobility of a pharmaceutical determined. The T g -endotherm's shape varies with the alloy's composition, T g increases approximately linearly with the mol% of nifedipine, b and x increase, and the activation enthalpy Dh à decreases. At T g , the relaxation time t cal of acetaminophen, nifedipine, and their alloys differs from 100 s to different extents. The distribution of relaxation times is lesser than that for polymers and other glasses. For a given composition, Dh à , b, x, and t cal anomalously depend upon the heating rate, indicating that variation of b with temperature would not yield better fits for modeling their stability. It is suggested that a pharmaceutical's relaxation is generally influenced by changes in intermolecular hydrogen bonds, chemical short-range order, vibrational frequency, isomerization, and impurity electrolyte dissociation, all of which contribute to the energy change with a distinctive kinetics.