Estimates of drug-related emergency department (ED) episodes and mentions reveal few significant changes from 2001 to 2002. Total drug-related ED episodes and mentions were statistically unchanged, while ED visits for any reason increased 2 percent. Over the long-term, drug-related ED episodes and their associated drug mentions grew at roughly twice the rate of total ED visits, with a 31 percent rise in drug-related ED visits, a 34 percent rise in ED drug mentions, and a 16 percent increase in total ED visits over the 8 year period 1995 to 2002. Among the 15 major substances of abuse, ED mentions of only 2 (PCP and amphetamines) increased significantly from 2001 to 2002, and 1 (LSD) declined. The most frequently mentioned drugs -- alcohol-in-combination, cocaine, marijuana, and heroin -- all remained stable. Among the most frequently mentioned other substances of abuse, the benzodiazepines were unchanged, while ED mentions of narcotic analgesics/combinations rose 20 percent from 2001 to 2002. Over the period 1995 to 2002, 8 of the 15 major substances of abuse -- alcohol-in-combination, cocaine, heroin, marijuana, amphetamines, MDMA (ecstasy), PCP, and GHB -- showed significant growth, while only 1 substance, LSD, showed a significant decrease. ED episodes involving marijuana have shown the largest percentage increase over the long-term. Of the less common major substances of abuse, amphetamines and methamphetamine form a middle tier in terms of numbers of drug mentions. ED mentions of amphetamines and methamphetamine in 2002 were concentrated in six metropolitan areas in the western United States. The remaining nine major substances of abuse, which form the bottom tier in terms of numbers of ED mentions, are primarily hallucinogens and club drugs MDMA, GHB, Ketamine, and Rohypnol. Drug abuse-related ED episodes involving certain prescription drugs, particularly the benzodiazepines and narcotic analgesics (pain relievers), continue to rise. 6 appendices, 340 tables, 18 figures