Also known as

yaba, tina and christine, meth, ice, glass, crystal meth, crank, batu, bikers coffee, black beauties, chalk, chicken feed, crystal, go-fast, hiropon, methlies quick, poor man's cocaine, shabu, shards, speed, stove top, tina, trash, tweak, uppers, ventana, vidrio, yellow bam, fire, nazi dope, gack, jib, tik, P




Methamphetamine is part of the amphetamine family of stimulant drugs. Different amphetamines differ in how powerful they are and how they are considered under the Misuse of Drugs Act [1].

The key effects and risks of methamphetamine include -

  • Feeling very up, exhilarated, alert and awake.
  • Feeling agitated, paranoid, confused and aggressive.
  • There's evidence that long-term methamphetamine use can cause brain damage, although this gradually gets better if the user stays off the drug for a long time [1].

The crystal form of methamphetamine, sometimes called Crystal Meth or Ice, is extremely powerful and addictive. Some compare it to 'crack cocaine' as both are smoked and give an intense, powerful 'high' followed by a very severe 'comedown', and both are very addictive [1].

What does it look like?

Usually comes in the form of crystalline whitish powder, although colourant may be added and pills also appear [2]. Methamphetamine is a sparkly, crystal-appearing rock structure that can be ground into powder and, when flaked, looks like small shards of glass. It is dissolvable in water or alcohol and is sometimes taken by drinking a dissolved mixture. There is no identifiable odour to the drug, although there are numerous odours associated with its manufacture, which can be housed in illegal home/garage types of laboratories [3].

It can come in several different forms - including tablets, powder, or crystals. The tablets are sometimes referred to as Yaba and the smokeable crystals are often called Crystal Methamphetamine or Ice [1].


Methamphetamine is a manmade, white, bitter-tasting powder. Sometimes it's made into a white pill or a shiny, white or clear rock called a crystal. Meth is made in the United States and often in Mexico - in "superlabs" - big illegal laboratories that make the drug in large quantities. But it is also made in small labs using cheap, over-the-counter ingredients such as pseudoephedrine, which is common in cold medicines. Other chemicals, some of them toxic, are also involved in making methamphetamine [4].

Most of the methamphetamine available on the street is made in secret, makeshift laboratories that may be found in ordinary kitchens, bathrooms, basements, or sheds. The ingredients used to make meth are fairly inexpensive, although they can be difficult to obtain. The process for making ('cooking') methamphetamine is not difficult to learn, so uneducated drug dealers can make the drug without any scientific training. Making methamphetamine is also incredibly dangerous; toxic fumes fill the labs, and explosions and fires are constant dangers [5].


There is a lack of prevalence data on the use of methamphetamine in the general population as routine monitoring in Europe does not distinguish amphetamine from methamphetamine. Methamphetamine is however a widely used psychoactive drug in North America and countries of the Far East. In Europe, amphetamine is more widely available than methamphetamine, use of which has historically been restricted to the Czech Republic and, more recently, Slovakia [6].

Globally, methamphetamine is the second most commonly used illicit drug, after cannabis [7].

According to The UNODC Word Drug Report 2015 -

The global market for synthetic drugs continues to be dominated by methamphetamine. The increasingly diversified market for methamphetamine is expanding in East and South-East Asia, where it accounts for a large share of the people receiving treatment for drug use in a number of countries, and use of crystalline methamphetamine is increasing in parts of North America and Europe [7].

UK Situation

According to the 2016 Home Office statistics, methamphetamine use was reported in 0.2% of adults, reflecting the belief that this drug has not taken off as much in the UK as in other parts of the world [7].

Street price

In 2011, the methamphetamine retail price reported by a few countries varied from EUR 8 (Lithuania) to EUR 79 (Germany) per gram [6].

Why take it?

Sought after effects

  • euphoria,
  • increased energy,
  • talkativeness,
  • heightened libido [2],
  • increased alertness,
  • concentration,
  • enhance self-esteem,
  • appetite suppressant [8].

Undesired effects

  • panicky,
  • obsessive,
  • excessive sweating,
  • sexually irresponsible [2],
  • irritability,
  • paranoia,
  • confusion,
  • diarrhoea,
  • nausea,
  • loss of appetite,
  • insomnia,
  • tremors,
  • jaw-clenching,
  • agitation,
  • talkativeness [8].


The precise causes for addiction have yet to be determined, so most researchers believe that methamphetamine addiction is caused by a number of factors. These factors include -

  • genetic - individuals who have a close relative such as a sibling or parent who struggles with addiction are more likely to develop an addiction later in life.
  • biological - as the brain of chronic methamphetamine users slowly begins to deteriorate and becomes unable to naturally produce pleasurable sensations, methamphetamine addicts require the drug to feel any sort of pleasure.
  • environmental - individuals who grow up in a home that is rife with addiction are more likely to see drug abuse as a way to cope with emotional problems, which can lead to addiction later down the road.
  • psychological - many individuals who struggle with methamphetamine addiction have an untreated or undiagnosed mental illness. To manage the symptoms of the mental illness, some individuals do turn to substances to 'self-medicate' the symptoms [9].

How long do its effects last?

Onset of effects

  • oral - 20 - 70 minutes [10].
  • nasal - 0 - 2 minutes [10].
  • intravenous - 1 - 2 minutes [10], 0 - 2 minutes [11].

Come up

  • oral - 20 - 70 minutes (dependant on form and stomach contents) [11].
  • nasal - 5 - 10 minutes [11].
  • vaporised - 0 - 2 minutes [11].


  • oral - 3 - 5 hours [10].
  • nasal - 20 minutes [10].


  • oral - 3 - 4 hours [10].
  • nasal - 1 hour [10].
  • intravenous - 3 - 4 hours [10].

Duration of effects

  • oral - 3 - 5 hours [11].
  • nasal - 2 - 4 hours [11].
  • vaporised - 1 - 3 hours [11].
  • intravenous - 4 - 8 hours [11].

Coming down

  • oral - 2 - 6 hours [11].
  • nasal - 2 - 6 hours [11].
  • vaporised - 2 - 4 hours [11].
  • intravenous - 2 - 4 hours [11].


  • oral - 12 - 24 hours [10], up to 24 hours [11].
  • nasal - 6 - 12 hours [10], up to 24 hours [11].
  • intravenous - 12- 24 hours [10], up to 24 hours [11].
  • vaporised - up to 24 hours [11].


Methamphetamine produces similar effects to the central nervous system as other stimulants, but with fewer peripheral effects. Methamphetamine's lipophilicity allows it to cross the blood brain barrier much quicker than other stimulants.

The main active ingredient or metabolite of methamphetamine in the body is amphetamine, but there are other metabolites that are also released, including 4-hydroxymethamphetamine (pholedrine), norephedrine and 4-hydroxynorephedrine.

Methamphetamine acts on a range of neurotransmitter systems in the brain; serotonin, noradrenaline and dopamine. It acts by inhibiting their re-uptake in a very similar way to MDMA. Components of a neuron work to remove a neurotransmitter once they have been used by the neuron, and methamphetamine reduces their function, so causes an increase in the levels of these neurotransmitters. It also increases the activity of the dopamine-synthesising enzyme tyrosine hydroxylase, which in turn produces more dopamine [2].

Methamphetamine is a CNS stimulant that causes hypertension and tachycardia with feelings of increased confidence, sociability and energy. It suppresses appetite and fatigue and leads to insomnia. Following oral use, the effects usually start within 30 minutes and last for many hours. Later, users may feel irritable, restless, anxious, depressed and lethargic. It increases the activity of the noradrenergic and dopamine neurotransmitter systems. Methamphetamine has higher potency than amphetamine, but in uncontrolled situations the effects are almost indistinguishable. The S-isomer has greater activity than the R-isomer. The therapeutic dose of the S-isomer is up to 25 mg orally. It is rapidly absorbed after oral administration, and maximum plasma levels are in the range 0.001 - 0.005 mg/L. The plasma half-life is about nine hours. The major metabolites include 4-hydroxymethamphetamine and amphetamine. Fatalities directly attributed to methamphetamine are rare. In most fatal poisonings the blood concentration is above 0.5 mg/L. Analysis of methamphetamine in urine is confounded because it is a metabolite of certain medicinal products (e.g. selegiline). Acute intoxication causes serious cardiovascular disturbances as well as behavioural problems that include agitation, confusion, paranoia, impulsivity and violence. Chronic use of methamphetamine causes neurochemical and neuroanatomical changes. Dependence - as shown by increased tolerance - results in deficits in memory and in decision-making and verbal reasoning. Some of the symptoms resemble those of paranoid schizophrenia. These effects may outlast drug use, although often they resolve eventually. Injection of methamphetamine carries the same viral infection hazards (e.g. HIV and hepatitis) as are found with other injectable drugs such as heroin. When methamphetamine is smoked it reaches the brain much more quickly. Drugs which are smokable (e.g. methamphetamine, crack cocaine) are much more addictive and more likely to cause problems when consumed in this way than when taken orally [12].

Methamphetamine affects the CNS by acting as a releasing agent for neurotransmitters such as dopamine, norepinephrine, and serotonin. It also acts as a reuptake inhibitor, increasing levels of monoamines by forcing the neurotransmitters out of their storage vesicles and expelling them into the synaptic gap by making the dopamine transporters work in reverse [13], [10]. Other mechanisms by which methamphetamine are known to increase monoamine levels are by -

  • blocking the reuptake of monoamines by inhibiting the activity of monoamine transporters,
  • decreasing the expression of dopamine transporters at the cell surface,
  • increasing cytosolic levels of monoamines by inhibiting the activity of monoamine oxidase (MAO),
  • increasing the activity and expression of the dopamine-synthesizing enzyme tyrosine hydroxylase (TH) [10].

In addition to releasing potent amounts of monoamines, MA has a high lipid solubility which leads to a relatively fast transfer of the drug across the blood brain barrier and a quick onset in comparison to other stimulants [14]. All of this results in feelings of reward, euphoria and stimulation and an unpleasant offset [10].


Methamphetamine undergoes hepatic metabolism via several mechanisms. When catalysed by cytochrome P450 2D6, methamphetamine undergoes N-demethylation (producing amphetamine) and aromatic hydroxylation (producing 4-hydroxymethamphetamine). Beta-hydroxylation produces norephedrine. The various metabolites resulting from the metabolism of methamphetamine do not significantly contribute to its effects on the human body [15], [16].

70% of a dose of methamphetamine is excreted in urine within 24 hours [17]. The terminal plasma half-life of methamphetamine of approximately 10 hours is similar across administration routes, but with substantial inter-individual variability. Acute effects persist for up to 8 hours following a single moderate dose of 30 mg… via vapour inhalation (smoking), methamphetamine bioavailability ranges from 67% to 90%... [and] is 79% bioavailable via the intranasal route [18], [11].

Route of administration

People generally have a preferred way of administering methamphetamine, often favoured because of a desired higher bio-availability, and sometimes for the ritual(s) it involves -

  • smoking - Methamphetamine is smoked, either out of a glass pipe composed of a a bowl and stem, or off foil. This is the most common ROA due to high bio-availability 90.3% without the risks of injection, or the discomfort of insufflation or plugging.
  • insufflation - Just as snorting most other substances, This produces a quick, but short-lived peak followed by a few hours of coasting. Many users report the effects of insufflation last much longer than smoking. The bio-availability is a surprisingly low 79%.
  • injection - This is a popular ROA among long time users for its quick intense rush and the 100% bio-availability. The risks of injecting street methamphetamine are very high. A regular user is at risk of developing a PE, a blockage of the main artery of the lung or one of its branches, and commonly develop skin rashes (also known as 'speed bumps') or infections at the site of injection. One also risks putting 'cut' into their veins when this is done.
  • oral - This ROA is often used for its discreet nature. Users will sometimes empty Tylenol capsules and fill them with methamphetamine for public use. This is the safest way to ingest methamphetamine, presenting the least amount of risk factors. The only common factor being the substance itself, not taking into consideration each person's individual risk factors. Oral bio-availability of methamphetamine is 62.7%.
  • plugging - This is an uncommon ROA, due to the stigma associated with putting drugs into the rectum (outside medical contexts). Plugging methamphetamine involves inserting the drug into the anus (or vagina) directly, via capsule, or by dissolving it in water and using a hypodermic syringe with the needle removed to squirt the resulting methamphetamine solution into the rectum. Some users report increased sexual satisfaction with this method of administration. Methamphetamine will have a fairly easy onset with a high peak, a long coast and an easy comedown. The bio-availability of suppository methamphetamine use is 99% [19].


Approximately 10 hours for all ROA [18].

As it metabolises, methamphetamine has a half life of nine to 12 hours. This means that the amount of time for the body to eliminate one half of the substance is that period [3].


Methamphetamine is excreted from the system by the kidneys, while the pH of the urine determines how much of the drug remains at the time of removal. For methamphetamine administered orally, 30% - 54% will remain as unaltered methamphetamine, while 10% - 23% will process as unaltered amphetamine. For drugs taken by injection, 45% passed from the body will remain unchanged methamphetamine and only 7% will synthesise as unaltered amphetamine. The drug is 62.7% available via administration through ingestion, 79% through nasal inhalation, 90.3% available when smoked, and 100% when injected through intravenous use [3].

Methamphetamine is metabolised by a liver enzyme and is excreted by the kidneys in urine. It is metabolised to amphetamine, p-OH-amphetamine, and norephedrine.

When taken orally, concentrations of methamphetamine peak in the bloodstream between 2.6 and 3.6 hours and the amphetamine metabolite peaks at 12 hours.

If meth is taken intravenously, the elimination half-life is a little longer, about 12.2 hours [20].

Lethal dosage

In mice the LD50 is 70mgs intraperitoneally [18].


  • a need for increased amounts of methamphetamine to achieve intoxication or the desired effect. You have to increase doses amount or frequency in order to maintain effective craving management and pain relief.
  • diminished effect on the user with continued use of the same amount of meth. In other words, when you take the prescribed amount of methamphetamine, no therapeutic effects occur. Likewise, if you are taking methamphetamine recreationally, increased tolerance would manifest as no euphoric effect [21].
  • full tolerance is reached rapidly develops with prolonged and repeated use,
  • decreases to half after 3 - 7 days,
  • returns to baseline after 1 - 2 weeks,
  • cross-tolerance with all dopaminergic stimulants [10].

Mechanism of action

Methamphetamine causes a quick release of the neurotransmitter dopamine in the brain, producing feelings of extreme pleasure, sometimes referred to as a 'rush' or 'flash'. It is important to note that when you do fun drug-free things like listen to music, play video games, or eat tasty food, the brain naturally releases small amounts of dopamine, making you feel pleasure. But meth floods the brain with dopamine, depleting its supply. So, once the effects have warn off, the brain will no longer send the small amounts of this pleasure producing chemical to the brain when you do ordinary activities, and that can lead to depression.

Regular use of methamphetamine causes chemical and molecular changes in the brain, sometimes for a long time. The activity of the dopamine system changes, causing problems with feeling pleasure, movement, and thinking [4].

Mode of use

Depending on its form, methamphetamine can be swallowed, snorted or injected; and unlike amphetamine, it can also be smoked.

Injecting methamphetamine, and sharing needles, syringes or other injecting equipment, runs the risk of the injector catching or spreading viruses, such as HIV or hepatitis C. There is also the risk that veins may be damaged and of abscesses or clots developing.

The effects of methamphetamine can last a very long time and can be followed by a severe come-down. Smoking the purer, crystalline form of methamphetamine, Crystal Meth, produces a very intense 'high' similar to that produced by [[Cocaine][crack cocaine]] but much longer lasting - a period of between 4 and 12 hours when you're not really in control [1].

Methamphetamine may be ingested, snorted and, less commonly, injected or smoked. Unlike the sulphate salt of amphetamine, methamphetamine hydrochloride, particularly the crystalline form (ice), is sufficiently volatile to be smoked. When ingested, a dose may vary from several tens to several hundreds of milligrams depending on the purity and the isomeric composition [12].

Methamphetamine is swallowed, snorted, injected with a needle, or smoked. 'Crystal meth' is a large, usually clear crystal that is smoked in a glass pipe. Smoking or injecting the drug delivers it very quickly to the brain, where it produces an immediate and intense high. Because the feeling doesn't last long, users often take the drug repeatedly, in a 'binge and crash' pattern [4].

Snorted up the nose, smoked, injected, or sometimes as a suppository (anal or vaginal) [8].

Signs of usage

There are several indicators that can help identify a person who has been abusing methamphetamine. Methamphetamine abuse can cause insomnia, anxiety, and violent or psychotic behaviour. If this type of behaviour is not typical for that person, he or she may have a drug problem. Chronic methamphetamine users also often display poor hygiene, a pale, unhealthy complexion, and sores on their bodies from picking at 'crank bugs' - the tactile hallucination that tweakers often experience. In addition, users may have cracked teeth due to extreme jaw-clenching during a methamphetamine high [6].

  • dilated (enlarged) pupils,
  • talkativeness,
  • restlessness and agitation,
  • aggressiveness, paranoia and psychosis,
  • anxiety and panic attacks,
  • increased heart rate (tachycardia) and faster breathing,
  • jaw clenching and teeth grinding,
  • dry mouth,
  • sweaty/clammy skin [22].


Methamphetamine makes users feel very up, alert and energised as well as agitated, paranoid, confused and aggressive [1]. It can also have other effects -

  • Increased levels of activity and feelings of arousal.
  • Reduced appetite.
  • Increased heart rate and blood pressure, raising the risk of heart attack - the higher the dose, the greater these effects.
  • Lowered inhibitions, which can lead to users taking risks that they wouldn't normally take, such as having unsafe sex [1].

The effects of methamphetamine can last a very long time and can be followed by a severe come-down. Smoking the purer, crystalline form of methamphetamine, Crystal Meth, produces a very intense 'high' similar to that produced by [[Cocaine][crack cocaine]] but much longer lasting - a period of between 4 and 12 hours when you're not really in control [1].

Short-term effects

The following effects are traits that methamphetamine users demonstrate while under the influence of the drug -

  • brief rush,
  • euphoria,
  • surge of energy,
  • increased physical activity,
  • increased blood pressure,
  • increased breathing rate,
  • dangerously elevated body temperature,
  • loss of appetite,
  • sleeplessness,
  • paranoia,
  • irritability,
  • unpredictable behaviour,
  • performing repetitive, meaningless tasks,
  • dilated pupils,
  • heavy sweating,
  • nausea,
  • vomiting,
  • diarrhoea,
  • tremors,
  • dry mouth,
  • bad breath,
  • headache,
  • uncontrollable jaw clenching,
  • seizures,
  • sudden death [6],
  • depression,
  • anxiety,
  • unpredictable behaviour; violence,
  • acne,
  • cracked teeth,
  • weight loss,
  • sores and skin infections,
  • damaged nerve terminals in the dopamine-containing regions of the brain [5].

Physical effects

  • abnormal heartbeat,
  • appetite suppression,
  • bronchodilation,
  • dehydration,
  • frequent urination,
  • stamina enhancement,
  • increased blood pressure,
  • increased heart rate,
  • increased perspiration,
  • nausea,
  • stimulation,
  • teeth grinding,
  • temporary erectile dysfunction,
  • vasoconstriction [10].

Long-term effects

These negative effects can onset during or after methamphetamine intoxication -

  • damaged nerve terminals in the brain,
  • brain damage similar to Parkinson's or Alzheimer's Diseases,
  • high blood pressure,
  • prolonged anxiety,
  • paranoia,
  • insomnia,
  • psychotic behaviour, violence, auditory hallucinations and delusions,
  • homicidal or suicidal thoughts,
  • weakened immune system,
  • cracked teeth,
  • sores,
  • skin infections,
  • acne,
  • strokes,
  • heart infections,
  • lung disease,
  • kidney damage,
  • liver damage,
  • increased risk behaviour, especially if drug is injected,
  • when used by a pregnant woman, premature birth; babies suffer cardiac defects, cleft palate, and other birth defects,
  • death [6],
  • tooth decay,
  • inability to function socially,
  • lowered resistance to disease,
  • lead poisoning,
  • brain damage similar to Alzheimer's disease or Parkinson's disease,
  • increased risk of contracting HIV/AIDS and hepatitis B and C [5].

Cognitive effects

  • anxiety,
  • cognitive euphoria,
  • compulsive redosing,
  • depression,
  • irritability,
  • time distortion,
  • analysis enhancement,
  • ego inflation,
  • empathy, love, and sociability enhancement,
  • focus enhancement,
  • increased libido,
  • increased music appreciation,
  • memory enhancement,
  • motivation enhancement,
  • stamina enhancement,
  • thought acceleration,
  • thought organisation,
  • wakefulness,
  • cognitive fatigue,
  • motivation suppression,
  • thought deceleration [10].

Visual effects

  • brightness alteration,
  • drifting,
  • double vision,
  • transformations [10].


  • full tolerance is reached rapidly develops with prolonged and repeated use,
  • decreases to half after 3 - 7 days,
  • returns to baseline after 1 - 2 weeks [10].


A methamphetamine overdose may result in a wide range of symptoms and is potentially fatal at heavy dosages [23]. A moderate overdose of methamphetamine may induce symptoms such as: abnormal heart rhythm, confusion, dysuria, high or low blood pressure, hyperthermia, hyperreflexia, myalgia, severe agitation, tachypnea, tremor, urinary hesitancy, and urinary retention [24]. An extremely large overdose may produce symptoms such as adrenergic storm, methamphetamine psychosis, anuria, cardiogenic shock, cerebral hemorrhage, circulatory collapse, hyperpyrexia, pulmonary hypertension, renal failure, rhabdomyolysis, serotonin syndrome, and a form of stereotypy ('tweaking'). A methamphetamine overdose will likely also result in mild brain damage due to dopaminergic and serotonergic neurotoxicity [25]. Death from fatal methamphetamine poisoning is typically preceded by convulsions and coma [10].


The most dangerous stage of methamphetamine abuse occurs when an abuser has not slept in 3 - 15 days and is irritable and paranoid. This behaviour is referred to as 'tweaking', and the user is known as the 'tweaker'. The tweaker craves more methamphetamine, but it is difficult to achieve the original high, causing frustration and unstable behaviour in the user. Because of the tweaker's unpredictability, there have been reports that they can react violently, which can lead to involvement in domestic disputes, spur-of-the-moment crimes, or motor vehicle accidents.

A tweaker can appear normal - eyes clear, speech concise, and movements brisk; however, a closer look will reveal that the person's eyes are moving ten times faster than normal, the voice has a slight quiver, and movements are quick and jerky [26]. These physical signs are more difficult to identify if the tweaker has been using a depressant such as alcohol; however, if the tweaker has been using a depressant, his or her negative feelings - including paranoia and frustration - can increase substantially. A person should use extreme caution when dealing with an individual on methamphetamine [6].


Taking methamphetamine involves some serious risks [1]. Here's what it could do to you -

  • severe psychoses caused by methamphetamine have been reported in countries where there is widespread use of the drug. Psychosis is a serious mental state where you lose touch with reality and may come to believe things that are not true,
  • there's evidence that long-term use can damage the brain, although this gradually gets better if the user stays off the drug for a long time,
  • in cases of overdose - stroke, and lung, kidney and gastrointestinal damage can develop, and coma and death can occur,
  • inhibitions are lowered and libido may be increased - this can lead to taking part in risky activities that you would not normally do, such as having unsafe sex, which itself can lead to other risks, such as catching a sexually transmitted disease or an unplanned pregnancy [1].

Methamphetamine use increases your risk of -

  • dehydration,
  • malnutrition,
  • exhaustion,
  • stroke,
  • heart problems,
  • kidney problems including kidney failure,
  • lung problems,
  • dental issues such as increased sensitivity, cracked teeth, cavities and gum disease,
  • if injected, methamphetamine use is associated with vein problems, abscesses and bacterial infections.
  • unprotected sex, which may result in a sexually transmitted infection or an unintended pregnancy [22].


High potential for abuse and dependence -

  • psychosis,
  • violence,
  • overdose,
    • seizures,
    • coma,
    • death [8].


High potential for abuse and dependence -

  • obsessive behaviour,
  • 'meth mouth' - loss of teeth related to crystal meth use,
  • tolerance (needing more of the drug to get the same effect),
  • withdrawal symptoms including -
    • depression,
    • drug-related psychosis (may last for months or years after drug use is discontinued) [8].


It's not unusual for drugs to have things added to them to increase the weight and the dealer's profits. They can be cut with other amphetamines (like speed), caffeine, ephedrine, sugars (like glucose), starch powder, laxatives, talcum powder, paracetamol and other drugs with some similar effects.

Some impurities can be added by mistake, as impurities can be formed during the manufacturing process for methamphetamine.

Reports say that methamphetamine purity is generally low at 9% [1].

Tablets may contain up to 40 mg of active drug. The free base constitutes 80% of the hydrochloride salt. The retail purity of methamphetamines in 2011 ranged from 16% (Estonia and Denmark) to 82% (Turkey) in European countries reporting information. In Europe, the most common cutting agents are caffeine, glucose and other sugars, less commonly ephedrine or ketamine. Methamphetamine has been seen as an adulterant in ecstasy tablets [12].


Can you get addicted

The simple answer is - yes. For some people, methamphetamine use can lead to very strong psychological and physical dependence, especially if it is injected or smoked.

This usually means they have 'cravings' for methamphetamine, and a very strong drive to keep on using it despite evidence of accumulating harms.

Crystal Meth is the most potent and long-lasting form of methamphetamine - and when it is smoked it can be particularly dangerous and addictive [1].


Methamphetamine use for extended periods leads to tolerance and dependence. Stopping such chronic methamphetamine use, especially abruptly and/or after long term use at high doses can cause -

  • extreme fatigue,
  • tiredness,
  • depression,
  • sleep disruptions [27], [19].


Prolonged methamphetamine use leads to tolerance and extreme psychological dependence. Withdrawal from methamphetamine can produce -

  • anhedonia,
  • irritability,
  • impaired social functioning,
  • intense craving for methamphetamine [28], [29], [19].


Methamphetamine withdrawal varies depending on the level of addiction and frequency of methamphetamine use. However, symptoms develop within a few hours to several days after cessation of or reduction in heavy and prolonged use of methamphetamine [30]. Suddenly stopping chronic methamphetamine use may cause an array of withdrawal-related psychological and behavioral symptoms, and the most common symptoms are -

  • insomnia,
  • significant depression,
  • anxiety [11].

Another hallmark of methamphetamine withdrawal is impairment on a battery of cognitive functions; these include -

  • impaired memory,
  • divided and directed attention,
  • impaired motivation and planning [11].

Other common effects of withdrawal include -

  • hyperphagia,
  • agitation,
  • vivid and unpleasant dreams,
  • reduced energy [11].
  • restlessness,
  • poor concentration,
  • irritability [31].
  • nervousness,
  • gradual reversal of the pleasurable feelings induced by the drug [30].

People who try to quit using methamphetamine might experience very uncomfortable feelings of withdrawal, including -

  • get really tired but have trouble sleeping,
  • feel angry or nervous,
  • feel depressed,
  • feel a very strong craving to use methamphetamine [4].

How long do methamphetamine withdrawal symptoms last?

Withdrawing from methamphetamine can be hard, but the unpleasant feelings and physical sensations will not last forever. Withdrawal usually lasts from 1 to 2 weeks, but it can last upwards of 4 weeks (in some extreme cases, longer).

Methamphetamine withdrawal is most severe in the acute phase of withdrawal, peaking during the first 24 hours and usually declining by the end of the first week of abstinence. Also known as the 'sleep, eat, and drink' stage, your body and brain are in healing overdrive. Depressive and psychotic symptoms may also accompany acute withdrawal from methamphetamine, but usually resolve within a week, or so.

Following the acute withdrawal phase most withdrawal symptoms remain stable and at low levels for the remaining couple of weeks of abstinence. However, while the physical symptoms may resolve quickly, craving is also present. Cravings for methamphetamine are so difficult because of the extreme euphoria can induce. Most cravings last at least 4 - 5 weeks. This is where psychological and methamphetamine can induce. Most cravings last at least 4 - 5 weeks. This is where psychological and behavioural treatments can help [30].

Methamphetamine withdrawal timeline

Withdrawal from methamphetamine will be different for different people. The intensity of the symptoms experienced can depend on a few things such as how much you were using, your general health, any existing mental health issues and the length of time you were using methamphetamine. Here is a basic outline of how and when the signs of methamphetamine withdrawal appear. Please note that these are generalisations - not everyone will experience every single symptom within these windows of time [30].

  • 24 - 72 hours - In this period of time you'll probably feel exhaustion, need to sleep longer and feel depressive. Be on the lookout for extreme anxiety, panic, or suicidal thinking. Report any feelings of paranoia or hallucinations. These symptoms can be treated. Supportive medical interventions during acute detoxification and withdrawal are effective.
  • Week 1 - After a week, strong cravings for methamphetamine can appear. A feeling of hopelessness is common during this time, as are mood swings, anxiety, irritability, tiredness, agitation, sleep problems, poor concentration, aches, pains and headaches. You can also expect to feel hunger which can trigger rapid weight gain.
  • Week 2 - In two weeks you may still experience mood swings, depression, sleep problems and cravings. Other withdrawal symptoms can remained stable and at low levels for the remaining few weeks of abstinence.
  • Weeks 3 - 4 - After a month you should start to feel much better. Sleep patterns will improve, your energy levels will get better, and the mood settles [30].

Drug testing

Methamphetamine is absorbed by the body quickly, whether administered orally, inhaled, or injected. It crosses the blood-brain barrier and is rapidly distributed throughout the body. While it mimics other stimulant drugs, it is more soluble than others, making its effects more pronounced and impactful. It metabolises into the blood at peak rates after three to six hours and is fully metabolised by the liver after 10 - 24 hours [3].

Types of drug tests for methamphetamine

Methamphetamine presence can be detected in urine, sweat or saliva. Plasma is tested to determine toxic levels in those who overdose on methamphetamine in a hospital setting. In cases where there is a traffic accident or death outside a hospital setting, forensic units will perform blood tests to determine the presence of methamphetamine in the person(s) involved. While some popular (Internet) sources state that taking zinc supplements will mask the presence of methamphetamine in the urine, it is only recently that researchers from John Jay College of Criminal Justice determined that they were often, but not always, accurate. Tests may be performed to determine the source (whether pharmaceutically produced or illegally) of the methamphetamine. In some of these tests, it can be determined whether the substance is produced using Vicks Inhalers [3].

Limitations of drug tests for methamphetamine

Results for tests to determine methamphetamine use vary in effective time frames that will give accurate information about use. With a urine test, use within three to five days will be indicated. A hair sample will show even one use of methamphetamine for up to 90 days from the time of use, and blood or saliva testing will show use for one to three days after use [3].

How long is methamphetamine detectible in urine?

Meth can show up in a urine test from 1 - 4 days [20].

How long does methamphetamine remain in blood?

A blood test can detect meth for 1 - 3 days [20].

How long does methamphetamine show up in saliva?

Methamphetamine will show up in a saliva test for 1 - 4 days [20].

How long does methamphetamine stay in hair?

Methamphetamine, like many other drugs, can be detected with a hair follicle drug test for up to 90 days [20].


  • Methamphetamine is a Class A drug - so it's illegal to have for yourself, give away or sell.
  • Possession is illegal and can get you up to seven years in jail and/or an unlimited fine.
  • Supplying someone else, even your friends, can get you up to life imprisonment and/or an unlimited fine [1].

What if you're caught?

If the police catch you with methamphetamine, they'll always take some action. This could be a formal caution, or arrest and possible conviction [1].

  • A conviction for a drug-related offence could have a serious impact. It can stop you visiting certain countries - for example the United States - and limit the types of jobs you can apply for [1].

Did you know?

  • Like drinking and driving, using methamphetamine and driving is illegal - and you can still be unfit to drive the day after using methamphetamine. You can get a heavy fine, be disqualified from driving or even go to prison.
  • Allowing other people to supply drugs in your house or any other premises is illegal. If the police catch people supplying illegal drugs in a club they can potentially prosecute the landlord, club owner or any person concerned in the management of the premises [1].

Mixing with other drugs

Mixing methamphetamine with alcohol can have serious consequences - as the stimulant effects of methamphetamine and the depressant effects of alcohol interact unpredictably, which can increase the risk of harm or even death [1].

Mixed with other drugs, the dangerous side effects of methamphetamine can become incrementally more dangerous, and sometimes lethal, without warning. It is very important that those who are using/abusing methamphetamine understand the sometimes synergistic effects of methamphetamine when introducing other medications and/or street drugs [3].

  • anti-psychotics - When combined with anti-psychotics, methamphetamine renders them ineffectual. They become substantially ineffective, to the point of seizure activity and return of psychosis.
  • alcohol - While methamphetamine use/abuse creates stress on the heart and can cause heart problems in long-term use, mixing methamphetamine with alcohol increases this risk greatly. It will also mask the symptoms of drinking to the extent that those who are well past the defined limit and are legally drunk will not believe themselves to be so and will drive or do other things that they would not normally do when drinking alcohol alone.
  • benzodiazepines - Many users will attempt to take benzodiazepines to counter the side-effects of methamphetamines. Like alcohol, the effects may not match the amounts taken into the body and overdose is a possibility. Benzodiazepines are strong drugs, and using them with methamphetamines may allow the user to develop an addiction they do not realize they have. When stopping the benzodiazepines, it is necessary to taper off usage, or serious problems may occur. A doctor should be consulted if use goes on for any length of time.
  • marijuana - Use of marijuana while on methamphetamines can create increased risks for serious paranoia and psychosis. It is common for those who are attempting to come down from methamphetamine to use marijuana to cut down the side-effects. However, paranoia and psychosis may ensue.
  • antidepressants - Antidepressants taken along with methamphetamine have serious and dangerous side-effects. Those can include extreme high blood pressure, overheating, heart attack, stroke, and kidney failure. The interaction of these two drugs in the brain is counter-effective, and needs to be reported to a doctor.
  • heroin - Using methamphetamine with heroin or other opiates is a recipe for disaster. Without knowing that the drugs are working, because they can dilute the effects of each other, overdose may occur easily. The high from the heroin does not allow the user to know how much methamphetamine is too much and vice versa. Under the influence of either of these drugs, the other drug is not felt until it is too late. Heart attacks are a common cause of death from this lethal mix. There may also be heart damage done by the increased heart rate that methamphetamine causes, combined with the lowered heart rate caused by heroin or other opiates [3].

Methamphetamine used with any other central nervous system stimulant, even caffeine, can be lethal, because it not only increases the effects of both drugs, but combines to incrementally and synergistically build one upon the other and can be three or four times more fatal than either drug alone [3].

Harm reduction

The side-effects are similar to those of amphetamine but they can be more intense. Paranoia and edginess are common with this drug especially when it starts to wear off. The drug effects can last too long for some users, with insomnia lasting as long as 24 hours or more after taking the drug.

Users of methamphetamine also tend to chase the first high they get and extend the experience for considerable periods. This adds to the side-effects and makes the 'crash' far worse when it comes.

Amphetamines were originally developed as a slimming aid and methamphetamine is an appetite suppressant. This may be considered a benefit for some users but can lead to malnutrition in heavy users. Smoking the drug may also damage the lungs. Snorting may cause some nasal damage. There is strong anecdotal evidence that chronic methamphetamine use is damaging to dentition.

Methamphetamine is not physically addictive like heroin; however it can be strongly psychologically addictive. Users can become dependent on using the drug with use becoming more and more frequent; tolerance also develops with users needing to take more to get the same effect. When this happens, the side-effects also increase and heavy users can develop 'amphetamine psychosis', a condition that may lead to a temporary schizophrenic episode.

The psychological compulsion to reuse methamphetamine is very strong resulting in protracted 'binge' using.

This can be magnified by a lack of sleep, which often accompanies heavy use. Withdrawal from high doses can lead to severe depression.

Methamphetamines are often associated with polydrug use, often including alcohol. Most stimulant users use some form of 'come down' drug, such as cannabis or benzodiazepines/tranquillisers.

Methamphetamines and other amphetamines should not be taken in combination with the group of drugs known as Monoamine Oxidase Inhibitors (MAOI's), a group of anti-depressants with stimulant action or Ayahuasca, as the mix is potentially dangerous. Check with your doctor if you are not sure whether your prescription medication is an MAOI. Methamphetamine is also contraindicated with the use of retroviral drugs and combination therapies. As methamphetamine is perhaps widely used on the gay drug scene, this should be made explicit to at risk individuals.

When methamphetamine is injected and any injecting equipment is shared (needles, syringes, spoons, filters, tourniquets or other paraphernalia), there is a risk of contracting Hepatitis B and C, HIV (which can lead to AIDS) and other blood-borne diseases. These viruses are extremely resilient, and normal cleaning will not eliminate them, particularly in the case of Hepatitis, which can live outside the body in optimal laboratory conditions for three months. People who are infected with these viruses usually appear healthy, and may not develop the disease for years. From the moment someone is infected however, they carry the virus in their blood, and can infect others through sexual intercourse (particularly with HIV) and sharing any injecting equipment, even spoons and filters. The risk of sexual infection with the hepatitis C virus is very small. Methamphetamine can cause damage to the immune system.

Injecting Methamphetamine can be dangerous because of variations in purity and because of the compulsive use nature of the drug due to the dopaminergic effects. It can put the circulatory system under intense strain [2].

How you can inject more safely

Those who inject can protect themselves from HIV/AIDS and Hepatitis by always using clean equipment, obtainable from needle exchanges and some chemists, and not sharing with anyone else [2].


Small bags of white powder or crystals or syringes. Other items that could be left behind after meth abuse are small pieces of crumpled aluminum foil, drink cans with a hole in the side or the shafts of inexpensive ball-point pens that might be used to snort the drug [32].

  • if the drug is snorted - a razor blade will be used to chop it on a hard level surface such as a mirror or a sheet of glass or a tile. A tube or rolled banknote will be used as a 'Pipe'.
  • if injected - syringe and needle, water, tourniquet.
  • if smoked - matches and tinfoil [8].


Methamphetamine (as distinct from amphetamine) was first synthesised from ephedrine by the Japanese scientist Nagai Nagayoshi in 1893. However, it was not until 1919 that another Japanese scientist, Akira Ogata, managed to synthesise it in the crystalline form in which it is most commonly known today.

During the Second World War, amphetamine and dextroamphetamine (UK and US) and methamphetamine (Germany and Japan) were all used extensively to give greater stamina and tolerance to the psychological traumas of warfare to soldiers. It is reputed that as many as 40 million tablets of Pervitin and Isofan (both containing methamphetamine) were deployed to German troops and airmen during the Blitzkrieg of 1939 - 41. Methamphetamine was given to US troops serving in the Korean War (1950 - 3).

During the 1960's, as ever more substances were restricted in the US, production of methamphetamine began to go underground, and was increasingly used recreationally as 'crystal meth'. This trend quickly spread to the UK and Europe, and the smoking of it gained popularity in the 1980's, although the incidence of injecting has also increased due to the faster acting and more intense effects.

Although methamphetamine was originally scheduled as a Class B substance under the Misuse of Drugs Act 1971, due to a recommendation to the Home Secretary by the Advisory Council on the Misuse of Drugs in May 2006, methamphetamine was raised to Class A substance in 2007 [2].

Methamphetamine was first synthesised in Japan in the late 1800s from ephedrine, a drug commonly used to treat asthma.

Medically produced amphetamines (including methamphetamine) were used in Japan, Britain, Germany and the US during the Second World War to enable soldiers to stay awake and focussed.

From 1942, Adolf Hitler received daily injections of methamphetamine from his personal physician, Dr Theodor Morell.

The sale of methamphetamine products from retail pharmacists was banned in the UK in 1968. However, in the US the drug is available in pharmaceutical form for the treatment of ADHD and narcolepsy [7].

We begin with the discovery in China of a stimulant that was in a rare herb called Ma huang. This stimulant was used in Chinese medicine for over 5000 years. It's not until the late 1800 that scientists are able to isolate the source of the stimulation. Nagayoshi Nagai was able to isolate ephedrine as the source of the stimulant properties of the Ma huang. 2 years later in 1887 Lazar Edelano is able to synthesis an ephedrine-like amphetamine called phenyisopropylamine. This and other findings and experiments lead to the creation of methamphetamine in 1893 by none other than the one able to isolate the ephedrine to begin with, chemist Nagayoshi Nagai. It's not until 26 years later that Akira Ogata was able to create crystallized methamphetamine.

American Gordon Alles of UCLA is able to reproduce Edelano's results and synthesise phenyisopropylamine in America. This patent is then sold to Smith, Kline and French and marketed as Benzedrine. The public is able to freely abuse Benzedrine throughout the great depression and WWII. Benzedrine is reformulated into tablet form as a treatment for narcolepsy in 1937 and one year later methamphetamine is released to the German public as Pervitin. Most countries involved in WWII on both sides experimented and gave methamphetamine to soldiers to increase alertness for long missions and battles. This was taking place in the late 1930's and quietly at present day methamphetamine and amphetamines are used by most militaries throughout the world.

The first methamphetamine epidemic takes place in Japan between 1945 - 1950 it spreads to Guam and the US Marshal islands. Later on in the 1950's and 1960's methamphetamine is marketed throughout the world as 'pep pills' and sold for non-medical reasons. In the 1950's methamphetamine was used by Korean doctors to treat soldiers morphine addiction not to mention during the 1960's that San Francisco drug clinics prescribed injections of methamphetamine to treat heroin abuse.

It wasn't until 1970 that the US Congress decided to regulate methamphetamine and other drugs through passage of the Controlled Substances Act (essentially the beginning of the drug war) this had an effect of forcing use and creation of the drug underground. It was during the 1980's that new syntheses were discovered and smoke-able forms of the drug were introduced to the world. This went on into the 1990's when the US Congress again moved on methamphetamine when in 1996 the comprehensive methamphetamine control act was passed regulating mail orders and the precursors necessary to produce methamphetamine [19].

Binge users

Binge abusers smoke or inject meth and experience euphoric rushes that are psychologically addictive [33].

  • Rush - the rush is the initial response the abuser feels when smoking or injecting meth and is the aspect of the drug that low intensity abusers do not experience when inhaling or swallowing the drug. During the rush, the abuser's heartbeat races and metabolism, blood pressure and pulse soars. Meanwhile, the abuser can experience feeling equivalent to 10 orgasms. Unlike the rush associated with crack cocaine, which lasts for approximately 2 - 5 minutes, the meth rush can continue for 5 - 30 minutes. The reason for the meth rush is that the drug, when smoked or injected, triggers the adrenal gland to release a hormone called epinephrine (adrenaline), which puts the body in a battle mode, for flight. In addition, the physical sensation that the rush gives the abuser most likely results from the explosive release of dopamine in the pleasure centre of the brain.
  • High - the rush is followed by the high. Sometimes called the shoulder. During the high, the abuser often feels aggressively smarter and becomes argumentative, often interrupting other people and finishing their sentences. The high can last 4 - 16 hours.
  • Binge - the binge is the continuation of the high. The abuser maintains the high by smoking or injecting more meth. Each time the abuser smokes or injects more of the drug, a smaller euphoric rush than the initial rush is experienced until, finally, there is no rush an no high. During the binge, the abuser becomes hyperactive both mentally and physically. The binge can last 3 - 15 days.
  • Tweaking - tweaking occurs at the end of the binge when nothing the abuser does will take away the feeling of emptiness and dysphoria, including taking more meth. Tweaking is very uncomfortable and the abuser often takes a depressant to ease the bad feelings. The most popular depressant is alcohol, with heroin a close second. Tweaking is the most dangerous stage of meth abuse cycle to law enforcement officers and other individuals near the abuser. If the abuser is using alcohol to ease the discomfort the threat to law enforcement officers intensifies. During this stage, the law enforcement officers must clearly identify the underlying dangers of the situation and avoid the assumption that the tweaker is just a cocky drunk.
  • Crash - to a binge abuser, the crash means an incredible amount of sleep. The body's epinephrine has been depleted, and the body uses the crash to replenish its supply. Even the meanest, most violent abuser becomes almost lifeless during the crash and poses a threat to no one. The crash can last 1 - 3 days.
  • Normal - after the crash, the abuser returns to normal - a state that is slightly deteriorated from the normal state before he used meth. This stage ordinarily lasts between 2 - 14 days. However, as the frequency of binging increase, the duration of the normal stage decreases.
  • Withdrawal - no acute, immediate symptoms of physical distress are evident with meth withdrawal, a stage that a abuser may slowly enter. Often 30 - 90 days must pass after the last drug used before the abuser realises that he is in withdrawal. First, without really noticing, the individual becomes depressed and loses the ability to experience pleasure. The individual becomes lethargic; he has no energy. Then the craving for more meth hits, and the abuser often becomes suicidal. If the abuser, however, takes more meth at any point during the withdrawal the unpleasant feelings will end. Consequently, the success rate for traditional meth rehabilitation is very low. 93% of those in traditional treatment return to abuse meth [33].


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