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Methamphetamine (also known as meth, chalk, crank, crystal meth and ice) is a synthetic drug manufactured from chemical ingredients. It belongs to a group of drugs called stimulants.
Methamphetamine is only produced illegally. It is often sold as a white powder that people sniff up the nose. The powder can also be mixed with water and injected. Methamphetamine also comes in the form of tablets that are swallowed or as crystals (crystal meth) that are smoked.
How quickly methamphetamine affects a person depends on how it is taken.
- The drug reaches the brain fastest if it is injected or smoked. Its effects are felt within seconds.
- Snorting takes 3 to 5 minutes for its effects to be felt.
- Swallowed as tablets, it may be 20 minutes before methamphetamine takes effect.
Short-term effects of methamphetamine
Methamphetamine can have dangerous and unpredictable short-term physical and mental effects.
People who take methamphetamine experience a temporary rush of well-being (euphoria). They also feel:
- higher energy and less fatigue
- increased wakefulness and alertness
- a rapid flow of ideas and speech
- a sense of great confidence
- decreased appetite
These effects generally last 6 to 8 hours, but can sometimes last up to 24 hours.
The short-term physical effects of methamphetamine include:
- dry mouth
- headache and dizziness
- stomach ache
- twitching muscles, problems breathing and shortness of breath (with crystal meth)
- increased blood pressure
- fast and irregular heartbeat
Long-term effects of methamphetamine
Over the long term, the drug can affect all body systems.
Methamphetamine increases the activity of important brain chemicals (dopamine and serotonin). This changes people's moods and mental state.
When the drug wears off, the most common effects of methamphetamine use are anxiety and depression. People who use methamphetamine may also be aggressive and violent.
In the long term, problematic use may cause any or all of these symptoms:
- trouble sleeping
- because methamphetamine is a strong stimulant, individuals frequently suffer from insomnia
- loss of memory
- a person may experience mental confusion, and have short or long-lasting memory problems
- brain damage
- some of the changes methamphetamine causes in the brain may be permanent
- the drug kills brain cells, and destroys the ability of the brain to produce its own chemicals
- hallucinations and delusions
- a person may see, hear or feel things that are not really there
- a common delusion is that insects are under their skin
- a person can experience erratic or bizarre thought patterns and completely lose touch with reality
- a person can feel threatened and believe others are trying to harm them
- suicidal feelings
- a person may sometimes attempt suicide, especially during withdrawal
All these mental problems and effects harm a person's ability to properly manage their lives.
Long-term physical effects of methamphetamine include:
- high fever
- chest pain
- heart attack
A range of further possible health harms can result from problematic use of methamphetamine, such as:
- poor nutrition
- methamphetamine suppresses the appetite to the point where a person is often unhealthily thin and undernourished, with brittle bones
- severely damaged skin
- methamphetamine (meth) mouth or extended dry mouth
- the lack of saliva allows bacteria to flourish, leaving a permanent bad taste in the mouth
- teeth are often blackened or stained, with many cavities
If methamphetamine is injected and individuals share drug supplies (such as needles, pipes or spoons), they risk serious infection. Several diseases can be spread by contaminated drug equipment, such as:
Methamphetamine use during pregnancy can be harmful to an unborn child. It is associated with:
- a decrease in the mother's appetite
- slow fetal growth, leading to low birth weight
- premature delivery
Whether by overdose or by long-term heavy use, methamphetamine can:
- cause convulsions that lead to death
- make the heart beat abnormally, eventually causing heart failure
- burst blood vessels in the brain, leading to permanent brain damage, coma or death
- suppress appetite so that the person becomes undernourished or anorexic and more vulnerable to infections
- cause failure of vital organs like the liver or kidneys
- cause changes in brain structure and function
Substance use disorders and withdrawal
Methamphetamine is highly addictive. As more of the drug is used, tolerance develops. This means that more and more is needed to experience the desired effects.
If methamphetamine use is stopped abruptly, the person experiences intense cravings. They are so intense that they cannot focus on anything else. Eventually, their lives may be taken over by the urge to get and use the drug.
Other symptoms of withdrawal include:
- intense fatigue
- difficulty sleeping or disturbed sleep
- feeling hungry all the time
- depression and irritability
The stage of methamphetamine use when a person comes down from a drug-induced state is commonly known as "tweaking." As the effects wear off, the person feels a powerful combination of:
- drug craving
- possible paranoia and hallucinations
This is a dangerous state, both for the individual and for those around them. The individual may be in a psychotic state or disconnected from reality. They can also become hostile and violent. They may self-mutilate, attempt suicide or attack others for no reason.
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