While the effects of amphetamines are almost immediate, tolerance is built up quickly, thus increasing the amount needed to produce the desired effect. During periods of nonuse, the user will recall the feeling of euphoria produced by the drug and desire to take it again.
According to the 2005 National Survey on Drug Use and Health (NSDUH), an estimated 10.4 million people age 12 or older (4.3 percent of the population) have tried methamphetamine at some time in their lives. A 2005 Monitoring the Future (MTF) survey of student drug use and attitudes study revealed that 4.5 percent of high school seniors reported using methamphetamines at some point in their life, along with 4.1 percent of tenth graders and 3.1 percent of eighth graders. Among high school seniors, 3.2 percent reported methamphetamine use in the past year. Both surveys showed recent declines in methamphetamine abuse among the nation's youth.
In contrast, evidence from emergency departments and treatment programs attest to the growing impact of methamphetamine abuse in the country. The Drug Abuse Warning Network (DAWN), which collects information on drug-related episodes from hospital emergency departments (EDs) throughout the nation, has reported a greater than 50 percent increase in the number of ED visits related to methamphetamine abuse between 1995 and 2002, reaching approximately 73,000 ED visits, or 4 percent of all drug-related visits in 2004.
