Methamphetamine, also known as "crystal," "crystal meth," "crank," "go-fast," and, in its smokable form, "ice" or "glass," is a member of the stimulant class of drugs, often referred to as speed. It is similar in effect to other amphetamines, but packs an even more intense punch.
Crystal meth was first seen in South Korea and Taiwan, and came onto the market as a legal appetite suppressant. It is still available in a prescription form to temporarily address obesity, although it's infrequently used for this purpose. The methamphetamine available on the street, however, is most often culled from underground labs, where the drug is cooked up in varying potencies and with differing purity. It usually appears as a white powder, or, in the case of ice, as whitish crystals. It is sometimes odorless, but it can also have a strong ammonia smell — the by-product of illegal, sketchy production in bootleg labs.
As with other stimulants, crystal meth decreases appetite, reduces fatigue, boosts alertness and confidence, and, at higher doses, creates feelings of exhilaration and euphoria. Users are usually talkative, energetic, and have a sense of well-being. When injected or smoked, it brings on an intense rush; this sensation is often what causes users to "chase" their high and use more and more crystal, increasingly often. This is part of what makes crystal so potently addictive.
Methamphetamines arouse the central nervous system, increasing heart rate and elevating blood pressure and body temperature. With repeated and/or high dose use, it can cause nausea, tremors, dizziness, hyperthermia (when the body temperature rises to dangerously high levels), heart failure, and stroke. Psychologically, meth can cause anxiety and hallucinations. Heavy users have also experienced something called toxic psychosis, a phenomenon in which the person feels panicked and paranoid, and may behave violently toward other people or themselves. They may also get seemingly stuck in repetitive physical movements or speech patterns. Although these symptoms usually resolve when the methamphetamine is cleared completely out of the body, they sometimes linger for weeks or even months. Scientists believe this is probably due to damage of neurotransmitters in the brain.
When crystal users go on a binge — what's called "amping" for days on end — they often experience poor nutrition, lack of sleep, and other nasty side effects of driving too fast for too long. Like using crystal's stimulant cousins cocaine and crack, "tweaking" can go on and on until the user has run out of money, is mentally confused and disoriented, is physically exhausted, or worse. Overdose on methamphetamine is highly possible, especially in this scenario.
Another factor to consider is that whether someone is smoking, swallowing, injecting, or snorting crystal meth, they're likely to be careless about other aspects of their health. In addition to lack of sleep and malnutrition, risk of HIV and Hepatitis B infection go way up if users share their needles to get a fix. Also, although stimulant use has been associated with difficulty maintaining an erection, methamphetamines seem to increase sex-drive. Feeling pumped and confident, some users engage in unsafe and/or rough sex, increasing their exposure to HIV, Hep B, and other STIs.
"Frozen," the symptoms you are experiencing might or might not be related to your crystal use. It's possible that your body is still recovering from its over-stimulation and, with proper nutrition and plenty of rest, the symptoms will subside. However, checking in with your health care provider and discussing your methamphetamine use and concerns could help to put your mind at ease. If your use is creating concerns for you (medical or otherwise), it might be a good time to examine the reasons you are using crystal (or any other drugs, for that matter), and how they're affecting your body, mind, and relationships.