A client has dilated pupils, appears jittery, and complains that “he just needs to get some sleep.” The client is most likely using which of the following substances?

Cocaine use is indicated by dilated pupils, hyperactivity, euphoria, anxiety, and/or excessive talking. Heroin use is indicated by contracted pupils, sleeping at unusual times, sweating, vomiting, twitching, and/or loss of appetite. Marijuana use is indicated by glassy, red eyes; inappropriate laughter; and/or loss of interest/motivation. Painkiller addiction is indicated by sleepiness, inattention, constipation, and/or loss of appetite.