Rechallenge, Potential Drug Induced Liver Injury (Kaiser)

Inclusion criteria

• Patients who received at least one prescription for a suspect drug between Jan 1, 2003 and June 30, 2009 (drug initiation period)
• Patients who experienced incident DILI event (identified by ALT ≥3xULN or AP ≥2xULN within 6 months of suspect drug administration) during the first exposure period that:

• Resolved to within normal limits of ALT (for hepatocellular & mixed) or AP (for cholestatic) within 180 days or
• Resolved to ALT < 3xULN (for hepatocellular & mixed) within 90 days or AP<2xULN (for cholestatic) within 180 days or
• Dropped by ≥50% of (Peak ALT - ULN) for hepatocellular or of (Peak AP - ULN) for cholestatic or mixed within 180 days
• Patients who were rechallenged with the same suspect drug; rechallenge will include first rechallenge event for the analysis.
• Patients who had at least of 12 months of continuous membership and drug benefit prior to and on the dispensing index date (inclusive). There is no minimum restriction of continuous membership plus drug benefit after the start date.
• Patients who were 18 years of age or older at the time of the first drug dispensing (index date) during the drug initiation period Jan 1, 2003 and June 30, 2009. Each patient's first prescription for the study drugs during the drug initiation period will be identified as index prescription.
• Patients who had health insurance coverage with full medical, pharmacy and lab benefits at the index date.

Exclusion criteria

• Patients meeting the definition of chronic liver injury and exhibiting persistent ALT≥3xULN or AP or bilirubin ≥2xULN within 90 days after initial injury
• Patients with chronic liver injury diagnostic codes or included in KPSC disease registries preceding the initial or rechallenge liver injury