Study of the EEG Changes during the Combined Ingestion of Alcohol and H1-antihistamines by using the Wavelet Transform

H₁-antihistamines affect the central nervous system (CNS) and, therefore, electroencephalographic (EEG) changes should be expected to occur. The principal aim of this work was to assess the effects on the EEG when hydroxyzine 10 mg (HY) and cetirizine 25 mg (CE) were administered with and without alcohol 0.8 g/kg (AL). Thirty-three healthy young subjects participated in two placebo-controlled trials. In the first one, 15 subjects received placebo (PL), HY and CE. In the second trial, 18 volunteers took PL, AL, and AL in combination with HY and CE. CNS effects of the different treatment conditions were evaluated at baseline, as well as at +4 h and +1 h post-medication for each study, respectively. EEG recordings from electrodes O1 and O2 were analyzed using the wavelet transform. Then, several entropies were calculated from wavelet decomposition to detect changes in the pattern of regularity of the signals. The obtained results suggest that the concomitant ingestion of AL with HY reduces the changes in the irregularity of the EEG, opposite to the behavior observed for CE. Hence, wavelet entropies could be useful descriptors of the EEG alterations induced by several drugs in a different way that the conventional Fourier-based methods.