After a user has abused meth, they can easily become addicted and seek increased doses or different methods of ingestion to maintain the same euphoric feeling. The body can build up a strong tolerance to the drug with repeated use, leaving an addict searching for a way to find a greater high. Typically users begin by snorting or swallowing the drug, but once a tolerance develops many will resort to a more direct route of administration such as smoking or injecting the drug. This causes the effects of meth to set in almost immediately and greatly increases the intensity of the drug. The rush from smoking or injecting meth makes using the drug many times more addictive than other routes of administration.
When a user becomes addicted or dependent on the drug, meth will often start having more serious psychological effects on the brain, especially when “coming down” off the drug. A binge user of meth will experience a high that lasts from four to sixteen hours after the initial rush. Many users will continue to use meth throughout this time and extend the binge to last several days. During the high period the user feels smarter and more aggressive, but as its effects die down they will become increasingly agitated, argumentative, and combative. This period of coming down is known as “tweaking”. Here, no amount of meth use will be able to bring back the rush that the user desires. This is typically when the serious psychological effects start to set in. A user will typically experience feelings of emptiness, depression, and paranoia. Some psychologists describe this experience as a meth-induced schizophrenia. Often times this causes hallucinations and feelings of bugs crawling underneath the skin. In the final stage of the come-down off meth, a user will experience a “crash”. This is when the body’s stores of epinephrine have been depleted and the user falls into a deep sleep, typically for one to three days.