Amphetamine Use Has Long-Term Effects

Young people who use drugs often take a careless approach, believing that their choices are a harmless part of adolescent freedom. Dangerous behaviors such as drug and alcohol use are especially risky for teens, because they often experience a delusion of invincibility, thinking that the risks associated with a certain behavior can’t apply to them.

A new study suggests that teens who use certain drugs may experience the negative consequences for many years to come. The study, conducted by researchers at McGill University Health Centre, provides evidence that there may be long-term problems associated with the use of amphetamines in adolescence.

Led by Dr. Gabriella Gobbi, the study examined how amphetamine use during the teen years can affect neurobiological processes, including risk-taking behavior, as the individual ages. The researchers found that the effects of amphetamines continue into adulthood, even if the individual long ago gave up drug use. The study’s findings are published in The International Journal of Neuropsychopharmacology.

The study’s findings are significant, because they provide some of the first information gained on the impact of long-term amphetamine use on behaviors and brain activity.

The research focused on how amphetamine use would affect certain neurotransmitters in adolescent rats, according to Dr. Gobbi, who is a researcher in mental illness and addiction at the Research Institute and is also an associate professor of medicine at McGill. Because the brain chemistry of rats is similar to humans, the study provided insights into how amphetamines might affect a human brain.

Amphetamine is often referred to as “speed” and is used as a way to increase focus. The United Nations Office on Drugs and Crime reported in 2011 that at least 10 percent of teens in the United States admitted to trying amphetamines.

The rats used in the study were administered one of three different dosing regimens during adolescence. Once the rats attained adulthood, the amphetamines were withdrawn and the researchers initiated an examination of their risk-taking behaviors and neurophysiological processes. The focus was on three specific neurotransmitters: serotonin, dopamine and norepinephrine.

The researchers found that there were abnormalities in activity relating to all three of the neurotransmitters. When these neurotransmitters are damaged, the result is emotional disturbances and disorders such as addictions or depression.

The study’s findings also reveal that there were behavioral differences in all three dosing groups. Risk-taking behavior was elevated in all three groups, and the rats who were administered moderate levels of amphetamine exhibited hyperactivity.