We used ITC to determine the binding free energy, enthalpy, and entropy, of five phenothiazine-based drugs with βCD and two methylated derivatives, H6M-βCD and H26DM-βCD, under uniform conditions of temperature and buffer. Interestingly, no binding was detected between any of the phenothiazines and the third derivative, HTM-βCD. The remaining results, averaged over the triplicate runs, are summarized in Tables 2-4 and Figure , while the Supporting Information provides enthalpograms, results of individual titrations, and concentrations used.