Pentoxifylline (PTX) inclusion complex with beta-cyclodextrin (beta-CD) was investigated by theoretical and experimental methods. Based on the PTX electronic absorption band variation in presence of beta-CD and using nuclear magnetic resonance experiments inclusion was verified. Data were confirmed by theoretical UV-Vis by means of TD-DFT calculations, demonstrating that beta-CD cavity was able to reduce the oscillator strength of some electronic transitions, and indicating a close range between internal beta-CD hydrogens to aliphatic PTX chain. Isothermal titration calorimetry experiments were useful to indicate that inclusion was spontaneous in solution. Additionally, at 298.15 K this inclusion process is enthalpic and entropic driven. (C) 2017 Elsevier B.V. All rights reserved.