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Latest revision as of 15:04, 23 April 2017

Contents

Also known as

Whizz, sulph, paste, billy, base, amphetamine sulphate, speed, phet, billy whizz, ice, crank, dex, dexies, fast, go fast, sulph, sulphate, uppers.

Classification

Stimulant

Overview

Amphetamines are strong stimulants that induce effects of euphoria, alertness, increased energy, appetite suppression and mental clarity. Due to these effects amphetamines were originally prescribed for slimming purposes, but were later deemed inappropriate due to the long-term side effects. However, certain amphetamines are increasingly being used in the treatment of ADHD [1]

Amphetamines can be divided into the following main types -

  • Amphetamine Sulphate (the 'L' variant) - 'speed' etc.
  • Dexamphetamine (the 'R' variant) - Ritalin etc.
  • Mixture of 'L' and 'R' variant such as 'Adderall'
  • Methamphetamine - 'crystal' [1].

There are a number of other amphetamine-type substances which we will not deal with here, and methamphetamine is dealt with separately here [1].

Speed is the street name for the Class B drug amphetamine sulphate. Sometimes speed is used to refer to other types of amphetamines.

Speed is a stimulant and people take 'speed' to keep them awake, energised and alert [2].

Other key effects and risks of taking speed are -

  • feeling 'up', excited and chatty,
  • people take it because it gives them the energy to do things for hours without getting tired, things like dancing, talking, and going out,
  • it can make people overactive, agitated or even acutely psychotic,
  • the high is generally followed by a long slow comedown, making you feel really irritable and depressed,
  • speed puts a strain on your heart and can cause heart problems - some people have died from taking too much speed [2].

Speed

The most common type of amphetamine, and one that is most commonly used recreationally, is the salt form: amphetamine sulphate ('speed'). It is usually a dull white colour, but may sometimes be other colours such as pink. It is usually sold in small paper packets called wraps. It is also available in a paste form which is usually white to grey or brown in colour and can be damp and gritty. This is sometimes inaccurately referred to as base, when it is actually paste.

Base should mean freebase amphetamine, which is an oily insoluble substance in water, is produced in the stage before the finished amphetamine sulphate salt and is usually stronger than the salt form.

Paste is a term given to the salt form that refers to the appearance of putty-like powder when it is damp. Much of the 'paste' volume (around 25% to 60%) is retained in a form of solvent, giving it that putty-like appearance.

The reason for the distinction is twofold; one that the paste form of amphetamine can be dried out and adulterated with usually caffeine or sugar, whereas base is much more difficult to cut, and two, consequently because of the first reason, base is usually stronger in purity than paste or salt [1].

Dexamphetamine

Dexamphetamine is approximately twice as strong, dose for dose, as amphetamine sulphate and can be prescribed in the UK - usually in 5mg tablet form. In the USA, 5, 10 and 15mg spansules (capsule that releases one or more medicinal drugs over time, in the body) of dexamphetamine are occasionally used for treating cocaine addiction.

There is a tendency for dexamphetamine tablets to be crushed for injection in the UK. This is a dangerous practice and should be avoided. For more advice, imcluding reduction, see our 'safer injecting' section here [1].


What does it look like?

Speed is usually an off-white or pinkish powder and can sometimes look like small crystals. The 'base' form of speed is usually purer and is a pinkish-grey colour and feels like putty [2].

The mainstay of the UK amphetamine market, amphetamine sulphate, is usually sold as a powder. Colour ranges from white, off-white, grey, yellow, and pink. It is usually sold by weight. This was typically in small rectangular wraps of paper, but increasingly now it is sold in self-seal bags. It is a sour-tasting, water soluble salt powder.

Increasingly commonly available is base-speed, a grey paste similar in consistency to putty or marzipan. It is a non-soluble base drug often smelling strongly of ammonia.

Dexedrine tablets are usually circular and are white or yellow. It is also sometimes prescribed as a linctus. Ritalin in tablet form is prescribed to children with ADHD and some of this is diverted to illicit use. Methamphetamine comes in the form of white powder or clear crystals, but is also sold in tablet form, though tablets are less common in the UK [3].

Source

Diverted from manufacturers, pharmacies, GPs, or made in clandestine laboratories in Britain and elsewhere and distributed through the illicit drug market [4].

Amphetamines are synthetic chemicals. There are a number of production routes. Some amphetamines are synthesised in clandestine labs in the UK, while the bulk of the rest is imported from mainland Europe.

Ritalin is prescribed in the UK for the treatment of ADHD and some diversion does occur.

There is a limited amount of Dexamphetamine prescribing, including to people with history of amphetamine dependency. However, there is minimal leakage from such prescribing to the street.

Historically, in the UK in the 50's, 60's and early 70's, medical diversion of amphetamines was much more widespread. Benzedrine inhalers were broken open and the drug extracted. Dexamphetamine was widely over-prescribed for weight loss and diverted to the streets. Stimulants were also a target for pharmacy thefts. The now-notorious drug methamphetamine was originally a branded pharmaceutical product and was marketed in the UK as 'Methedrine'. It was briefly and unsuccessfully used in London as a treatment for cocaine dependency.

In Eastern Europe, when the Warsaw Pact was still in place, a brand of methamphetamine called Pervitin was widely sold. As a term, Pervitin is still used in a number of countries including the Czech Republic. A cheap, crude form of methamphetamine, synthesised from ephedrine, has been reported in the media as a cheap street drug in Greece, sold as Sisa [3].


Street price

Speed is usually sold by weight, at a cost of around £5 per gram. Base is more expensive, typically £20 - £40 a gram. Methamphetamine - wide range of cited prices, from £50 - 200/g [3].

£5 per gram upwards [5].

Why take it?

Sought after effects

  • increased energy,
  • increased sex drive,
  • euphoria (intense happiness) at higher doses [1],
  • alertness,
  • confidence [4].

Undesired effects

  • reduced appetite,
  • restlessness,
  • loss of coordination (at higher doses) [1].
  • insomnia,
  • loss of appetite,
  • dry mouth [4].

Causes

Many addictions do not have a single identifiable cause. Rather, it's likely that amphetamine addiction is related to a number of interplaying factors. Some of these factors may include -

  • Genetic - Individuals who have a close genetic relative who struggles with addiction are more likely to develop an addiction later in their life.
  • Biological - It has been theorised that some individuals may have inborn defects in the reward pathway in the brain. This may cause them to attempt to seek out pleasurable substances such as amphetamines in order to self-medicate to feel more normal.
  • Environmental - Many individuals who grow up in households where addiction is present learn through modeling that substance abuse is the appropriate way to manage stress. In addition, individuals who are pressured by outside sources to do better and be better may begin to abuse stimulants to keep up with the demands placed upon them.
  • Psychological - A number of individuals who become addicted to stimulants may suffer from undiagnosed and untreated mental illnesses. Individuals who have perfectionistic tendencies may also succumb to usage of stimulants to achieve all that he or she desires [6].

What are the different forms?

Amphetamine comes in a variety of forms and varies in its purity [7].

Amphetamine sulphate

This is most common form of street amphetamine. It sometimes appears as a white, off white, sometimes pinkish crystal powder. This can be snorted, rubbed on the gums, dissolved in a drink or swallowed (wrapped in a cigarette paper). People may also dissolve it in water and inject it to produce a more powerful high. Injecting drugs carries particularly high risks of overdose, infections, addiction and damage to veins [7].

Amphetamine 'base'

In Europe this usually refers to a putty or paste containing amphetamine sulphate. The name is confusing, because amphetamine can occasionally be found in its 'freebase' chemical form, an oily liquid, but this is not what is usually meant by 'base'. So-called base amphetamine is often much stronger than the normal powder kind, although the purity of illegally produced amphetamine is so variable that you never really know [7].

Amphetamine pills

These come in various colours, shapes and markings. Sometimes pills sold as MDMA (ecstasy) or other drugs may actually contain amphetamine. As with the forms above, purity is variable and often low, with much of the pill being other substances which could themselves be harmful [7].

Prescription amphetamines

There are a range of prescription drugs containing amphetamine, related to amphetamine, or which are turned into amphetamine by the body. These are used to treat conditions such as ADHD or narcolepsy but have been known to end up being used recreationally [7].


How long do its effects last?

Onset of effects

  • oral - 20 - 60 minutes [8], 15 - 30 minutes [9].
  • nasal - 1 - 5 minutes [8].

Peak

  • oral - 3 - 6 hours [8].
  • nasal - 1 - 2 hours [8].

Offset

  • oral - 3 - 5 hours [8].

Duration of effects

  • oral - 6 - 8 hours [8], 2 - 4 hours [9].
  • nasal - 3 - 6 hours [8], 1 - 3 hours [9].

After-effects

  • oral - 5 - 10 hours [8].
  • nasal - 5 - 24 hours [8].

Pharmacology

Amphetamine is a psychostimulant. This means that it works by increasing the activity in certain parts of the nervous system. Specifically, amphetamine increases the amount of dopamine, noradrenalin and serotonin in areas of the nervous system such as those involved in reward/pleasure, movement and thought/decision making (amongst others). The effects that amphetamine can have are both physical (e.g. increased heart rate) and psychological (e.g. increased confidence). Many other drugs are variations of the amphetamine molecule [7].

Amphetamine exerts its behavioural effects by modulating neurotransmitters in the brain, effecting the monoamine neurotransmitters dopamine, serotonin, and norepinephrine. Amphetamine and other amphetamine-type stimulants act principally to release dopamine into the synaptic cleft and the neurotransmitters dopamine and norepinephrine are released from nerve endings in the brain and their reuptake is either slowed down or inhibited. Consequently, a build up of these neurotransmitters at synapses in the brain accumulates. When nerve cells in the brain and spinal cord are activated by amphetamine, the mental focus, the ability to stay awake, and the ability to concentrate is improved, which is helpful for those with hyperactivity disorders or narcolepsy. Amphetamine is implicated in short-term reward and in the 'flight/fight' response in humans. The 'come-down' effect is consequently disorientating and unpleasant, interferes with the sleep pattern and can be implicated in impulsive and high-risk behaviours [1].

Amphetamine 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 noradrenaline and dopamine neurotransmitter systems. Amphetamine is less potent than methamphetamine, but in uncontrolled situations the effects are almost indistinguishable. The S-isomer has greater activity than the R-isomer. It is rapidly absorbed after oral administration. After a single oral dose of 10 mg, maximum plasma levels are around 0.02 mg/L. The plasma half-life varies from 4 to 12 hours and is dependent on the urinary pH: alkaline urine decreases the rate of elimination. A major metabolite is 1-phenyl-2-propanone, with smaller amounts of 4-hydroxyamphetamine. Analysis of amphetamine in urine is confounded because it is a metabolite of methamphetamine and certain medicinal products. Acute intoxication causes serious cardiovascular disturbances as well as behavioural problems that include agitation, confusion, paranoia, impulsivity and violence. Chronic use of amphetamine 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 amphetamine carries the same viral infection hazards (e.g. HIV and hepatitis) as are found with other injectable drugs such as heroin. Fatalities directly attributed to amphetamine are rare. The estimated minimum lethal dose in non-addicted adults is 200 mg [10].

Amphetamine is a full agonist of the trace amine-associated receptor 1 (TAAR1), which is a key regulator of common and trace brain monoamines such as dopamine, serotonin and noradrenaline. The agonism of this set of receptors results in the release of increased concentrations of dopamine, serotonin and noradrenaline in the synaptic cleft. This leads to cognitive and physical stimulation within the user [8].

Pharmacodynamics

Amphetamines increase the activity of monoaminergic systems. The primary mechanism is by increasing release of dopamine from nerve terminals [11], [12]. Amphetamines are thought to enter the nerve terminal via the transporter, disrupt storage vesicles of dopamine and reverse the direction of the dopamine transporter through which large amounts of dopamine are released [13]. The ability of amphetamines to release dopamine is dose-related [14].

In addition to this, amphetamines are able to inhibit dopamine metabolism and its reuptake. Amphetamines are able to increase the release of noradrenaline and serotonin [14], [15], [16], [17].


Pharmacokinetics

Amphetamines may be administered orally, intranasally or intravenously. The peak response occurs one to three hours after oral administration [18], or approximately 15 minutes after injection [19]. A single dose may maintain an effect for up to 7 - 12 hours [20]. However, when urine is alkaline (pH greater than 6.7), the half-life may increase to 18 - 34 hours [21], [22].

Amphetamines are metabolised by the liver by a range of enzymes, including cytochrome P450 2D6 [23]. [24]. Metabolites include 4-hydroxyamphetamine, 4 hydroxynorephedrine, hippuric acid, benzoic acid and benzyl methyl ketone [25], [26]. Methamphetamine is metabolised to amphetamine. Some amphetamines are also excreted unchanged in the urine [27].

Lethal dosage

The LD50 of amphetamine in rats has been found to be between roughly 15mg and 180mg per kilogram depending on the study. No formal studies in humans have been carried out and the exact toxic dosage is unknown [8].

Mechanism of action

Amphetamines have a number of mechanisms of action. The key effect is to elevate levels of the brain chemicals dopamine, nor-adrenalin (nor-epinephrine) and to a lesser extent serotonin [3]. They do this by -

  • pushing brain chemicals out of storage, increasing active levels in the brain.
  • preventing the reuptake of brain chemicals back in to storage,
  • inhibiting the enzymes that would normally break down brain chemicals [3].

Mode of use

Speed is either dabbed onto the gums, or is snorted in lines (like cocaine powder). Sometimes it's rolled up in a cigarette paper and swallowed, this is called 'bombing'. It can also be injected or mixed into drinks.

The effects of speed kick in within half an hour of swallowing. If you snort or inject speed it will kick in quicker - the effects can last for up to six hours.

Injecting speed, and sharing injecting equipment, runs the risk of the injector catching or spreading a virus such as HIV or hepatitis C. There is also the risk that veins may be damaged and that an abscess or a blood clot will develop [2].

Tablets can be swallowed, powders can snorted up the nose, dissolved in a drink, or swallowed (known as bombing). Both powders and tablets can prepared for injection. Methylamphetamine, or ice, can be smoked [4].

Amphetamine and methamphetamine pills can be ingested orally, crushed and snorted, dissolved in water and injected, or smoked (inhalation of the vaporised drug). 'Glass' and 'ice' (pure methamphetamine, which look like clear crystalline rock) is most often smoked (vaporised and inhaled) in a glass pipe, allowing for quick absorption into the bloodstream without the risks of injecting the drug. 'Crystal' the powder form of methamphetamines, is consumed orally, injected, or inhaled [28], [29].

  • Amphetamine sulphate - as a water-soluble drug, it can be readily snorted or rubbed on gums. However, it has a very unpleasant taste and is painful to snort so it is often wrapped in a cigarette paper and swallowed (bombed) to get it in with as little taste as possible. Speed powder is also injected. It requires no heating or acid but should be filtered (though rarely is).
  • Base speed - insoluble in water, though will melt in hot water. Injectors have caused significant complications by heating base speed in water and injecting it, where it tends to congeal on cooling. It is safer to dissolve base speed in hot water and drink it. But if it is to be injected, it needs to have an acid added to make a solution. It can be smoked.
  • Methamphetamine - a salt drug, which dissolves readily. It can be snorted, rubbed on gums or injected without heating or addition of acid. Unusually, although a salt, it can also be smoked.
  • Tablets - should be swallowed; if crushed for injecting should be filtered thoroughly [3].

Signs of usage

These effects are key indicators of amphetamine use, but could also be caused by other stimulants [3].

  • reduced appetite,
  • clenching jaws,
  • grinding teeth,
  • elevated heart rate and blood pressure,
  • dilated pupils,
  • increased perspiration,
  • insomnia,
  • talkative,
  • restlessness,
  • pacing [3].

Heavy prolonged use can result in nasal or tooth damage (depending on route), weight loss, insomnia and mental health problems [3].

Effects

Speed makes users feel very up, alert and energised, but can also make them agitated and aggressive [2]. It can also have other effects -

  • Speed makes people feel wide awake, excited and chatty.
  • Clubbers take it because it gives them the energy to dance for hours without getting tired.
  • Amphetamines were once the main ingredient in diet pills because they stop people feeling hungry.
  • Speed use can lead to agitation, panics or even a psychotic episode [2].

When swallowed the effects of amphetamine normally appear in around half an hour. This may be longer if someone has a full stomach. Snorting amphetamine usually produces effects in only a few minutes, and injecting amphetamine will cause effects almost instantly. The effects typically last for 4 - 8 hours, although the after-effects can last for several days.

Possible psychological effects of amphetamine include increased confidence, feelings of wellbeing, alertness, focus, and motivation. People using amphetamine will often become more chatty, sociable and may experience increased sex drive. If the drug enters the body quickly (especially through snorting or injecting) then it may also cause a 'rushing' euphoric feeling, which lasts for a short period of time.

The energising effects of amphetamine can reduce feelings of tiredness and have often been used by people who want to do something active, like dance, for long periods of time. As amphetamine can increase energy levels, motivation and focus, it has also been used as a performance enhancer. For instance, some people use amphetamine (often in the form of medications meant to treat ADHD) as a study aid to help them focus and work for long periods of time.

Potential undesirable effects include increased anxiety, irritability, aggression, restlessness and paranoia. Psychotic symptoms (like those suffered by people with schizophrenia) can occur when taking amphetamines. These can include paranoid thoughts or delusions, for example believing that people are spying on you or recording your movements, and/or hallucinations, for example hearing people talking about you or hearing music and noises that are not really there. Psychotic symptoms may happen during amphetamine intoxication and can last days or weeks after the intoxication phase of drug use.

Some people have become violent after taking amphetamine. Physical effects of amphetamine include: increased heart rates and constriction of blood vessels (higher blood pressure), increased energy, dilated pupils, a rise in body temperature, reduced appetite, and dry mouth.

The 'comedown' period after amphetamine use can last for a few days. People can feel tired, muddled, depressed, socially incapable, irritable, and anxious. Additionally people may experience insomnia and restlessness, twitching, muscle aches, and fluctuating temperature. At very high doses the after-effects can be severe, including vomiting, diarrhoea, and a psychosis similar to schizophrenia [7].

Short-term effects

  • high body temperature,
  • cardiovascular system failure,
  • hostility or paranoia,
  • irregular or increased heart rate/heart beat,
  • increased diastolic/systolic blood pressure,
  • increased activity/talkativeness,
  • euphoria,
  • heightened sense of well-being,
  • decreased fatigue/drowsiness,
  • decreased appetite,
  • dry mouth,
  • dilated pupils,
  • increased respiration,
  • heightened alertness/energy,
  • nausea,
  • headache,
  • palpitations,
  • altered sexual behaviour,
  • tremor/twitching of small muscles [28],
  • release of social inhibitions,
  • unrealistic feelings of cleverness, great competence, and power [29].

Long-term effects

  • toxic psychosis,
  • physiological and behavioural disorders,
  • dizziness,
  • pounding heartbeat,
  • difficulty breathing,
  • mood or mental changes,
  • unusual tiredness or weakness,
  • cardiac arrhythmias,
  • repetitive motor activity,
  • convulsions, coma, and death,
  • ulcers,
  • malnutrition,
  • mental illness,
  • skin disorders,
  • vitamin deficiency,
  • flush or pale skin,
  • loss of coordination and physical collapse [29].

Physical effects

  • bronchodilation,
  • pupil dilation,
  • spontaneous tactile sensations,
  • stamina enhancement,
  • stimulation,
  • appetite suppression,
  • perception of decreased weight,
  • abnormal heartbeat,
  • dehydration,
  • frequent urination,
  • increased blood pressure,
  • increased heart rate,
  • increased perspiration,
  • nausea,
  • teeth grinding,
  • temporary erectile dysfunction,
  • vasoconstriction [8].


Cognitive effects

  • anxiety,
  • cognitive euphoria,
  • compulsive redosing,
  • depression,
  • irritability,
  • time distortion,
  • analysis enhancement,
  • ego inflation,
  • focus enhancement,
  • increased libido,
  • increased music appreciation,
  • memory enhancement,
  • motivation enhancement,
  • stamina enhancement,
  • thought acceleration,
  • thought organisation,
  • wakefulness,
  • cognitive fatigue,
  • dream suppression,
  • motivation suppression,
  • thought deceleration [8].

Visual effects

  • brightness alteration,
  • drifting,
  • double vision,
  • transformations [8].

Side-effects

Rare

  • seeing, hearing, or feeling things that are not there,
  • severe mental changes [30].

Common

  • decreased interest in sexual intercourse,
  • difficulty having a bowel movement (stool),
  • dry mouth,
  • hives or welts, itching, or skin rash,
  • inability to have or keep an erection,
  • loss in sexual ability, desire, drive, or performance,
  • loss of appetite,
  • redness of the skin,
  • unpleasant taste,
  • weight loss [30].

Incidence not known

  • blurred vision,
  • dizziness,
  • false or unusual sense of well-being,
  • fast, irregular, pounding, or racing heartbeat or pulse,
  • headache,
  • nervousness,
  • pounding in the ears,
  • restlessness,
  • shakiness in the legs, arms, hands, or feet,
  • slow or fast heartbeat,
  • trouble sleeping,
  • twitching, twisting, or uncontrolled repetitive movements of the tongue, lips, face, arms, or legs,
  • uncontrolled vocal outbursts or tics (uncontrolled repeated body movements) [30].

Positive effects

  • increased focus,
  • abundance of energy,
  • increased motivation [9].

Negative effects

  • racing thoughts,
  • reduced appetite,
  • flushing of the face,
  • increased body temperature,
  • tachycardia,
  • hypertension,
  • peripheral vasoconstriction (blood vessels get smaller in hands and feet making them susceptible to damage from cold),
  • paranoia,
  • insomnia [9].

After effects

  • anxiety,
  • appetite suppression,
  • cognitive fatigue,
  • depression,
  • irritability,
  • motivation suppression,
  • sleep paralysis - some users note sleep paralysis after consuming amphetamine,
  • thought deceleration,
  • wakefulness [8].
  • hangover,
  • afterglow,
  • restlessness,
  • persisting stimulation (5--15 hours after last dose) [9].

Overdose

  • abdominal or stomach cramps,
  • confusion,
  • dark-coloured urine,
  • diarrhoea,
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position,
  • fainting,
  • fever,
  • muscle cramps or spasms,
  • muscle pain or stiffness,
  • nausea,
  • seizures,
  • sweating,
  • unusual tiredness or weakness,
  • vomiting [30],
  • agitation,
  • increased body temperature,
  • hallucinations,
  • convulsions,
  • death [31].

Risks

Taking speed does involve risks. Here's what it could do to you -

  • Depending on how much you've taken, it can be difficult to relax or sleep.
  • The 'comedown', which can last a number of days, can make users feel really lethargic and down, and you can develop difficulty concentrating and with learning.
  • Speed puts a strain on your heart, so it's definitely not advisable for people with high blood pressure or a heart condition - users have died from taking too much.
  • Mixing speed with anti-depressants or alcohol has been known to kill.
  • Taking a lot of speed, alongside its effects on diet and sleep, can give your immune system a battering - so you could get more colds, flu and sore throats,
  • Speed can lead to anxiety, depression, irritability, aggression and paranoia; as well as mental illness, even to acute psychotic episodes.
  • Injecting speed is particularly dangerous. It's much easier to overdose when injecting. Speed is usually very impure, so it's not just the amphetamine that goes in to your bloodstream.
  • Injecting can also cause damage to veins and arteries, and may cause ulcers and even gangrene.
  • Viral hepatitis and HIV/AIDS infections can be spread by users sharing needles, syringes or other injecting equipment [2].

It is uncommon for people to die from an amphetamine overdose, although in some cases people have died from amphetamine induced strokes or heart attacks. This is because amphetamine raises blood pressure and constricts blood vessels. People at risk of heart disease or strokes are more likely to experience such complications from taking amphetamine.

Amphetamine in very large amounts can cause amphetamine psychosis and can make people paranoid, delusional and hallucinate. Some people have violently harmed themselves or others in a state of amphetamine psychosis. Additionally, some people have failed to fully recover from amphetamine psychosis and have had lasting symptoms. People taking amphetamine with a history (or family history) of mental health problems are more likely to develop amphetamine related mental health problems.

Some people may inject amphetamine, which carries much higher risks including the chance of getting HIV, hepatitis, or bacterial infections. If you choose to inject despite the added dangers, the risks can be reduced by using new needles and injecting equipment. You can get these from needle exchanges, which may be found in pharmacies or hospital [7].

  • Overdose/death - amphetamines put a significant strain on the cardiovascular system and can cause death through heart failure. Amphetamine was a feature in 120 deaths in the UK in 2013. This is low compared to opiates but the rate has increased year on year since 2010 [3].
  • Weight loss - heavy prolonged use of amphetamines can cause significant and dangerous weight loss. In turn this can lead to organ damage, and compromised immune system.
  • Nasal/tooth damage - highly acidic amphetamine erodes and weakens teeth and, when rubbed on gums can cause tooth loss. It also irritates and damages nasal tissue when snorted. Smoked methamphetamine causes significant tooth damage leading to a condition called 'meth mouth'.
  • Swallowing amphetamine - although safer than other routes, amphetamine can irritate and damage the stomach lining and may cause stomach damage.
  • Risk taking behaviour - amphetamines can cause over-confidence, irritability and possible aggression. It can contribute to increased violent episodes, especially in night-time economy settings. Amphetamines can also increase libido and the use of methamphetamine in the 'chemsex' scene has caused increasing concern. Chemsex is a term used to refer to drug-related sex activity, especially amongst Gay men, and is associated with the use of methamphetamine, and increased incidence of high-risk sexual activity.
  • Mental wellbeing - amphetamine causes an unpleasant comedown. Low levels of dopamine post use can cause low mood, depression, craving and dysphoria. Comedown also tends to leave the person feeling tired, run down, irritable and anxious. Even single episodes of use can lead to an unpleasant comedown - amphetamine is generally a drug that leaves the user feeling pretty low the next day. Some people will use other drugs (cannabis, benzos, alcohol) to take the edge off a comedown. Others will use more speed, leading to multi-day speed binges. The crash off extended use is inevitably far worse.

Amphetamines can cause anxiety and paranoia. With extended use, the combination of amphetamine use and sleep deprivation can lead to serious symptoms - hallucinations, delusion, paranoia and panic. The condition, often referred to as amphetamine psychosis doesn't usually persist once use stops and the person starts to eat and sleep again. However, symptoms can last for a number of days and possibly weeks, and may require inpatient treatment [3].

Short-term

  • anxiety,
  • paranoia,
  • tolerance [4].

Long-term

  • psychosis,
  • psychological dependence [4].

Purity

It's not unusual for drugs to have things added to them to increase the weight and the dealer's profits. Speed can be cut with other cheaper amphetamines, 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 speed.

Speed is usually a very impure street drug - most of the powder in a wrap only contains 5% - 15% amphetamine sulphate. Base speed is usually somewhat purer [2].

Non-pharmaceutical products are highly variable in quality. Amphetamine sulphate powder in the UK is notorious for its low purity, typically between 5% and 10% pure.

Base speed, which was taken out of production earlier, tended to be higher purity, often around 40%. However, some suppliers made 'fake base' by adding oil and ammonia to low quality speed powder to give it the look and smell of base speed.

Crystal meth, made in small batches and sold in crystalline form, is harder to adulterate and tends to be higher quality [3].

As with previous years, the purity of amphetamine is low compared to drugs such as ecstasy. Even in the peak years, roughly 1997 - 2000, purity levels never rose above 15%; more usually they settle between 5% - 10% [32].

Addiction

Speed is an addictive drug - the more you take, the more you tend to want to take. If you take a lot on a regular basis you build a tolerance to the drug so that you need higher doses just to get the same buzz or just to feel 'normal'; this increases the risks associated with speed.

With regular use, you may increasingly take speed to avoid unpleasant withdrawals [2].

Amphetamine has a fairly high potential for addiction. Regular use of amphetamine is likely to lead to physical and psychological dependence on the drug. Habitual amphetamine use can become increasingly compulsive and out of control and users may experience withdrawal symptoms without it. Withdrawal symptoms are generally a rebound from the drug's physical and mental effects, so for amphetamine symptoms include: tiredness, hunger, irritability, and depression. Additionally amphetamine withdrawal can cause insomnia, mood swings, and cravings for the drug [7].

Dependence

Amphetamines can and do lead to dependency. Patterns of dependency in the UK are significantly different to other countries where methamphetamine dependency is a more significant issue. Many drug projects, especially in regions where there is entrenched amphetamine use, will have a small cohort of speed-dependent clients.

Early speed use is euphoric, rewarding and typified by binges. Most people learn to take long breaks from speed use and the unpleasant come-down is a big deterrent.

After sustained use, the person is liable to be significantly dopamine depleted and feel very tired. At this point speed use is less about reward and more about just being able to function. Speed becomes a tool to help the person get up and do things.

A fair proportion of the dependent speed users attending drug projects are older men, in poor physical health, who have been using for a number of years. Some agencies also report seeing younger people who may have ADHD who are self medicating with amphetamines some of whom have previously been prescribed Ritalin.

Interventions don't usually require medical input, though some research suggests use of anti-depressants to help reduce craving. The key interventions centre on craving management, and interventions to address the low levels of dopamine and the associated cravings.

Substitute prescribing isn't widespread in the UK but is still undertaken on a limited basis [3].


Dangerous interactions

Although many drugs are safe on their own, they can become dangerous and even life-threatening when combined with other substances. The list below contains some common potentially dangerous combinations, but may not include all of them. Certain combinations may be safe in low doses of each but still increase the potential risk of death. Independent research should always be done to ensure that a combination of two or more substances is safe before consumption [8].

  • Stimulants - Amphetamine can be potentially dangerous in combination with other stimulants as it can increase one's heart rate and blood pressure to dangerous levels.
  • Tricyclic antidepressants - Amphetamine may increase the effects of tricyclic antidepressants to dangerous levels.
  • 25x-NBOMe - Both the NBOMe series and this compound induce powerful stimulation and their interaction may cause severe side-effects. These can include thought loops, seizures, increased blood pressure, vasoconstriction, increased heart rate, and heart failure (in extreme cases).
  • Alcohol - It is dangerous to combine alcohol, a depressant, with stimulants due to the risk of excessive intoxication. Stimulants decrease the sedative effect of alcohol which is the main factor most people consider when determining their level of intoxication. Once the stimulant wears off, the effects of alcohol will be significantly increased, leading to intensified disinhibition as well as respiratory depression. If combined, one should strictly limit themselves to only drinking a certain amount of alcohol per hour.
  • DXM - This combination may cause increased heart rate and panic attacks.
  • MXE - Increased heart rate and blood pressure may occur.
  • Tramadol - This combination can increase the risk of seizures.
  • MDMA (ecstasy) - The neurotoxic effects of MDMA may be increased when combined with amphetamines.
  • MAOIs - This combination may increase the amount of neurotransmitters such as dopamine to dangerous or even fatal levels. Examples include syrian rue, banisteriopsis caapi, 2C-T-2, 2C-T-7, αMT, and some antidepressants.
  • Cocaine - This combination may increase strain on the heart [8].

Withdrawal

The sustained or repeat use of amphetamines can lead to physical and psychological dependence that will also result in withdrawal when the drugs are no longer being used. According to the http://www.ncbi.nlm.nih.gov/pubmed/19370579, when use of amphetamines abruptly stops, withdrawal symptoms quickly set in causing the brain and the body to go through a series of uncomfortable, not so pleasure some reactions both physically and psychologically.

Amphetamine use actually causes an initial spike in the creation of the natural hormones epinephrine and norepinephrine which is followed by a lowered production of these naturally occurring hormones over time. The result is a physical dependence that the body develops on amphetamines to cause this spike in the development of naturally occurring hormones to make the individual feel good or feel pleasure [33].

  • paranoia,
  • depression,
  • dream potentiation,
  • anxiety,
  • itching,
  • mood swings,
  • irritability,
  • fatigue,
  • insomnia,
  • intense craving for more amphetamine or other stimulants,
  • nausea,
  • vomiting [8].


Physical symptoms of amphetamine withdrawal

Physically, the body will go through a range of withdrawal symptoms when amphetamine use is abruptly stopped including a boost in hunger and extreme fatigue. Most people who use amphetamines tend to binge on the drugs feeling extensive highs followed by a crash and burn cycle that includes extreme fatigue and long periods of sleep [33].

Additional physical symptoms of amphetamine withdrawal include

  • oversleeping,
  • excessive hunger that doesn't go away,
  • pain and discomfort in the stomach as a result of overeating,
  • lack of coordination,
  • shaking and the potential for seizures,
  • dehydration,
  • tachycardia,
  • arrhythmia,
  • cardiac arrest [33].

Psychological symptoms of amphetamine withdrawal

With all the symptoms that the user experiences physically, one may overlook the psychological elements of withdrawal—that is unless you are the one experiencing the symptoms. Psychologically, the symptoms of amphetamine withdrawal can be different from one person to the next and may depend on the psychological well-being of the user prior to amphetamine use and other factors. The most common symptoms include panic attacks, increased paranoia and mood swings as well as major cravings for amphetamines [33].

Additional psychological symptoms of amphetamine withdrawal include

  • irritability,
  • short-temper,
  • hypersensitivity to light and sound,
  • drug cravings,
  • extreme mood swings similar to bi-polar disorder,
  • depression,
  • anxiety,
  • suicidal ideation,
  • realistic nightmares,
  • hallucinations,
  • sensory misperception,
  • auditory hallucinations,
  • psychosis that is similar to schizophrenia [33].

Timeline of Amphetamine Withdrawal

Amphetamines cause tolerance where more and more of the drug is needed to produce the desired effect and many amphetamine abusers will binge on the drugs for an extended amount of time, until they run out, or until they become extremely exhausted. The first symptom of withdrawals is fatigue because amphetamine abuse wreaks havoc on the body and the abuser may sleep for days. Extreme hunger or nausea, followed by agitation, depression, or anxiety tends to occur next, but, this depends on a number of factors including the physical and mental health of the abuser.

Within a few hours, withdrawal symptoms such as irritability, drug cravings, muscle aches or pains, lack of coordination, stomach discomfort, shaking, dehydration, rapid respiration, sweating, and rapid heartbeat can occur. Panic, paranoia, mood swings, suicidal ideations, and other more severe symptoms can also begin.

The acute symptoms of amphetamine withdrawals can last from 2--10 days but, some individuals take longer to stabilise physically and/or psychologically, especially for methamphetamine users. According to the National Institute on Drug Abuse, In studies of chronic methamphetamine users, severe structural and functional changes have been found in areas of the brain associated with/ /emotion and memory, which may account for many of the emotional and cognitive problems observed in these individuals.

Cravings, depression, insomnia and other mental health problems can last weeks or months after the last dose of amphetamine drugs [34].

What are the harms of amphetamine addiction and withdrawal?

Long-term use of amphetamines can cause very serious physical harm and devastate quality of life. The heart can be damaged, and heart-beat can become irregular. Long-term amphetamine use is associated with anhedonia; a general difficulty in finding pleasure in life without the drug, which may persist for some time after quitting the drug. It has also been associated with differences in the structure of the brain. From the available evidence it is difficult to establish to what extent brain differences and anhedonia are reasons that people become amphetamine dependant, or consequences of heavy amphetamine use. However, the second possibility should be taken seriously. The negative effects of long term use of amphetamines may be intertwined with the harms of adulterants in the amphetamine, and of poverty and chaotic lifestyles. Amphetamine dependant people often suffer from serious problems sleeping, poor nutrition and anorexia (from reduced hunger) and a resulting appearance of accelerated aging [7].

Drug testing

Trying to determine exactly how long amphetamine is detectable in the body depends on many variables, including which kind of drug test is being used. Amphetamine - also known as Biphematine, Delcobase, Desoxyn, Obetrol, Reds, Meth, Black Beauties, Crosses, Hearts - can be detected for a shorter time with some tests, but can be 'visible' for up to three months in other tests. can be detected for a shorter time with some tests, but can be 'visible' for up to three months in other tests.

Other factors that can come into play in tests being able to detect amphetamine is how frequent it has been taken, how much was taken, the amount taken, and the quality or potency of the drug.

Detecting amphetamine in the system is also dependent upon each individual's metabolism, body mass, age, hydration level, physical activity, health conditions and other factors, making it almost impossible to determine an exact time amphetamine will show up on a drug test [9].

The following is an estimated range of times, or detection windows, during which amphetamine can be detected by various testing methods -

How long is amphetamine detectable in urine?

Amphetamine can be detected in a urine test from 2 - 5 days [35], 1 - 4 days [9].

How long does amphetamine stay in the blood?

Blood tests for amphetamine can detect the drug for up to 12 hours [35], [9].

How long does amphetamine show up in saliva?

A saliva test can reveal amphetamine for 1 - 5 days [35], 3 days [9].

How long can amphetamine be found in hair?

Amphetamine, like many other drugs, can be detected with a hair follicle drug test for up to 90 days [35], [9].

Legality

  • Speed is a Class B drug and it's illegal to have, give away or sell. Speed that has been prepared for injection becomes a Class A drug and can get you tougher sentencing if you're caught with it or selling it.
  • Possession can get you up to five years in jail and an unlimited fine.
  • Supplying someone else, including your friends, can get you up to 14 years and an unlimited fine [2].

What if you're caught?

If the police catch you with speed, they'll always take some action. This could include a formal caution, arrest and prosecution.

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 [2].

Did you know?

Like drinking and driving, driving while under the influence of drugs is illegal - with some drugs you can still be unfit to drive the day after using. 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 [2].

Mixing with other drugs

Taking amphetamine with other stimulants such as ecstasy can result in very high blood pressure or body temperature. Amphetamines may also mask the effects or early warning signs of depressant drugs such as alcohol or heroin, allowing the user to accidentally overdose.

Amphetamine can be very dangerous if you have taken certain medications, for example some antidepressants (MAOI inhibitors) [7].

Amphetamine is used extensively alongside alcohol. The stimulant effects of amphetamine significantly reduce the sedating effects of alcohol, allowing for increased alcohol consumption. This increases the risk of alcohol-related liver damage. Alcohol continues to disinhibit and the increased confidence and assertiveness of amphetamine with the disinhibition of alcohol makes for a volatile combination [3].

Harm reduction advice

  • Injecting amphetamine is compulsive and even within the drug sub-culture, amphetamine injectors are often viewed with some suspicion and caution.
  • The drug is usually low purity and if injected should be filtered carefully.
  • The use of stimulant drugs has become very popular since the advent of 'rave/club' culture', be aware of the risk of using a range of stimulant drugs at the same time as the drug can put the heart under significant stress.
  • Be aware of the temptation, to use benzodiazepines and anxiolytics to come down from the 'jag', the effects of the drug wearing off. While this may have some benefits there are legal and dependence issues to consider. The come down will pass without using more drugs.
  • Be aware of the importance of nutrition and hydration, as amphetamines are appetite suppressants and all stimulants cause the body to over heat and sweat.
  • Many heavy speed users grind or 'gurn' their teeth and jaws. It's a bit of a give away and will damage tooth enamel. Amphetamine also causes pupil dilation which is sometimes very obvious.
  • Dose levels between pharmaceutical amphetamines and 'street' formulations can be difficult to work out. If you are concerned, take a small amount and increase allowing time for the body to metabolise. With injecting this is instantaneous, with snorting 5 minutes and 'bombing' or tablets will start to take effect after 20 minutes.
  • Do not mix speed with monoamine oxidase inhibitors (MAOIs), as they inhibit naturally occurring enzymes in the body, if you are on any medication check that it's not a MAOI. Some users do not like to mix amphetamines with hallucinogenic, others do. Be aware that you may be overloading your perception apparatus and potentially prolonging a bad trip [1].

Care

Amphetamine varies in strength and there have been spates of overdoses associated with strong batches, including so-called 'base' amphetamine (which is rarely 'base' in the chemical sense). Most 'amphetamine' available on the unregulated, illicit market contains more adulterants, fillers and other drugs than actual amphetamine. It may contain no amphetamine sulphate at all, as some other drugs mimic amphetamine's effects. These mimics might be more harmful. If you take it despite the risks, it is a good idea to try a small amount of the drug to see what it does and wait for the effects to peak before considering if you want more. Even if the amphetamine is pure, higher doses have greater risks [7].

Injecting

It is much easier to take too much amphetamine when injecting. Also, injecting carries a whole range of extra risks including infection and damage to veins [7].

Tolerance

If a person is taking amphetamine regularly they may develop tolerance. Requiring more of the drug to achieve the same effects suggests that the use of amphetamine is causing lingering changes in brain chemistry. Increasing tolerance is often a signpost on the transition between recreational and dependent drug use [7].

Being careful what, and how much, you are taking

Amphetamine varies in strength and there have been spates of overdoses associated with strong batches, including so-called 'base' amphetamine (which is rarely 'base' in the chemical sense). Most 'amphetamine' available on the unregulated, illicit market contains more adulterants, fillers and other drugs than actual amphetamine. It may contain no amphetamine sulphate at all, as some other drugs mimic amphetamine's effects. These mimics might be more harmful. If you take it despite the risks, it is a good idea to try a small amount of the drug to see what it does and wait for the effects to peak before considering if you want more. Even if the amphetamine is pure, higher doses have greater risks [7].

Paraphernalia

Illicit amphetamine is usually sold as 'grams' or in a paper wrap. 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 [4].

Trends

According to the Crime Survey for England and Wales for 2014 - 15, only 1.3% of 16 - 24 year olds reported speed use in the last year. This was marginally down on the previous year. Back in 1996 reported levels were almost ten times higher, with 11.8% reporting use in the last year [3].

History

Amphetamine was first synthesised in 1887, by the German chemist L. Edeleano and first marketed in the 1930's as Benzedrine. Because the drugs increase energy levels and suppress appetite, they were widely used by states during World War 2 to give a 'boost' to service personnel, and in the 1950's and 60's as slimming aids. They are now prescribed to those suffering narcolepsy and, especially in the US, to children diagnosed with 'Attention Deficit Hyperactivity Disorder'. British troops used 72 million amphetamine tablets in the Second World War and ATS (Amphetamine Type Stimulants) are still widely used in the military. The bombing raids over Iraq, in the Gulf War were, allegedly undertaken by many pilots using the drug to increase endurance. Many famous writers have used amphetamines for inspiration and the history of thought and literature and music in the 20th century would be quite different without their influence [1].


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