title: Scutellaria baicalensis decreases ritonavir-induced nausea.
abstract: BACKGROUND
  Protease inhibitors, particularly ritonavir, causes significant gastrointestinal disturbances such as nausea, even at low doses. This ritonavir-induced nausea could be related to its oxidative stress in the gut. Alleviation of drug-induced nausea is important in effectively increasing patients' compliance and improving their quality of life. Conventional anti-emetic drugs can only partially abate the symptoms in these patients, and their cost has also been a concern. Rats respond to nausea-producing emetic stimuli by increasing consumption of non-nutritive substances like kaolin or clay, a phenomenon known as pica. In this study, we used this rat pica model to evaluate the effects of Scutellaria baicalensis, a commonly used oriental herbal medicine, on ritonavir-induced nausea.
  
  
  RESULTS
  Rats treated with 20 mg/kg ritonavir significant caused increases of kaolin consumption at 24 to 48 hr (P < 0.01). Pretreatment with 0.3 and 3 mg/kg Scutellaria baicalensis extract significantly decreased ritonavir-induced kaolin intake in a dose-related manner (P < 0.01). Compared to vehicle treatment, the extract completely prevented ritonavir-induced kaolin consumption at dose 3 mg/kg. The area under the curves (AUC) for kaolin intake from time 0 to 120 hr for vehicle only, ritonavir only, SbE 0.3 mg/kg plus ritonavir, and SbE 3 mg/kg plus ritonavir were 27.3 g x hr, 146.7 g x hr, 123.2 g x hr, and 32.7 g x hr, respectively. The reduction in area under the curves of kaolin intake from time 0 to 120 hr between ritonavir only and SbE 0.3 mg/kg plus ritonavir, ritonavir only and SbE 3 mg/kg plus ritonavir were 16.0% and 77.7%, respectively.
  
  
  CONCLUSIONS
  Scutellaria baicalensis significantly attenuated ritonavir-induced pica, and demonstrated a potential in treating ritonavir-induced nausea.
authors.affiliation: Tang Center for Herbal Medicine Research, Pritzker School of Medicine, The University of Chicago, IL 60637, USA. haung@dacc.uchicago.edu
authors.forename: Han
authors.initials: H
authors.lastname: Aung
authors.forename: Sangeeta
authors.initials: S
authors.lastname: Mehendale
authors.forename: Wei-Tien
authors.initials: WT
authors.lastname: Chang
authors.forename: Chong-Zhi
authors.initials: CZ
authors.lastname: Wang
authors.forename: Jing-Tian
authors.initials: JT
authors.lastname: Xie
authors.forename: Chun-Su
authors.initials: CS
authors.lastname: Yuan