 Our study design is a prospective, density sampling case control study in which one hundred patients with non viral hepatitis will be recruited as our case. We use a questionnaire designed by the investigator in the survey of demographic background, education, and income status of the cases, as well as the frequency of use of the drug, total dosage used, where the drug was purchased, what the drug is used for, and whether they know of any adverse effect that the drug might have. If they had taken the drug within three months prior to this emergency visit, then they are asked to bring the drug in for examination. Examination of the drug includes the use of high performance liquid chromatography HPLC and if necessary, inductively coupled plasma mass spectrometry ICP mass. In contrast, our control group consists of subjects that are admitted to the ED due to trauma or fracture. For each case, they are matched with two subjects in the control group in both gender and age. They should also arrive within two days after the arrival of the case. All cases and controls are screened for viral hepatitis and serology must be negative before entering the study. The questionnaire is given to both groups. If more than one control is eligible to enter the study, then the control is chosen by a random draw in a hat. After this use of density sampling, we collect the data and logistic regression is used for analysis. 