Methamphetamine affects dopamine levels in the brain, causing a flood of the neurotransmitter that disrupts normal functioning. Dopamine is not only responsible for feeling pleasure, but also for motivation, movement, memory functions, learning, and reward processing. In short, meth makes a person feel good and makes them want to continue taking it to keep feeling this way.
Taking meth repeatedly can build up a tolerance to the drug that will then require a person to take higher doses more often to feel the same effects as before. It may become difficult to feel happy without meth, and withdrawal symptoms like anxiety, insomnia, fatigue, increased appetite, depression, and even psychosis can occur when it wears off. This is called drug dependence, which can form rather quickly with chronic meth abuse and even faster with binge use and escalating dosages.
Once dependence forms, changes are made in how the brain functions and to its chemical makeup and circuitry. Compulsive drug-seeking behaviors and a loss of the ability to control how much and how often meth is taken can occur. This inability to control meth use coupled with the changes made in the brain are some of the primary hallmarks of addiction.
Addiction can create a myriad of social, emotional, physical, and behavioral issues. When someone suffers from addiction to meth, getting the drug, using it, and recovering from it can consume them, and other activities take a backseat. Interpersonal relationships suffer as mood swings can be unpredictable, and the person may consistently shirk regular responsibilities and obligations. Grades and work output drop, and unemployment, financial strain, and homelessness can be the result of meth addiction. Meth abuse also leads to lowered inhibitions and an increase in risk-taking and possible suicidal behaviors.
Health problems generally crop up too. The Drug Abuse Warning Network (DAWN) publishes that over 300,000 people received medical treatment in an emergency department (ED) for meth abuse in 2022.
Short-term side effects of meth abuse and addiction also include the potential for a life-threatening overdose. The effects on the heart and central nervous system can overwhelm the system and lead to seizures, heart attack, stroke, dangerously high body temperature, agitation, irregular heart rate, difficulties breathing, kidney failure, coma, and even death. When meth is mixed with other drugs, the likelihood of an adverse reaction and possible overdose increases greatly.