Presents final estimates for 2001, with comparisons to 1994, 1999, and 2000. The revised estimates in this volume supersede the estimates published previously for 1994 through 2001. The Drug Abuse Warning Network (DAWN) relies on a sample of hospitals operating 24-hour emergency depts. (EDs) to capture data on ED visits induced by or related to substance abuse. DAWN data do not measure prevalence of drug use in the population, but the probability sample of hospitals is designed to produce representative estimates of ED drug episodes and drug mentions for the coterminous U.S. and for 21 metropolitan areas. Also provides trends by drug episodes by patient demographics and episode characteristics. Extensive charts, tables and graphs.