Amphetamine / 'Speed'

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What is amphetamine (speed)?

Amphetamine is a strong stimulant that can make people feel alert and energised. It also usually lifts mood.

Amphetamine has a varied history. It has often been given to soldiers in wars and at one point was used as a diet pill.


What are the different forms of amphetamine?

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

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.  

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.

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.

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.


How does amphetamine work as a drug in the body and brain?

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.


What are the effects of amphetamine?

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.


Does amphetamine have any medical uses?

Medications that contain amphetamine, or related drugs, are used to treat attention deficit-hyperactivity disorder (ADHD). At the right dose, such medications can help some people focus

Amphetamine and its derivatives are sometimes used to treat symptoms of narcolepsy, a condition where people become very sleepy and fall asleep at inappropriate times. 

Amphetamine/amphetamine like drugs may have potential uses as a last resort for treating depression, especially where people may have low energy and motivation. However, amphetamine’s potential for addiction and harm is considerable, so conventional antidepressants will almost always be more appropriate. 


What are the risks of using amphetamine? Can they be avoided or reduced?

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 hospitals. 


Are there health conditions that make amphetamine more dangerous?

Yes. Amphetamine is potentially more risky for people who have or are at risk of heart or circulation problems including high blood pressure. 

Amphetamines may worsen glaucoma due to changes it can have on blood pressure.

Additionally, amphetamine may be riskier for people with mental health problems. People with schizophrenia or a history of psychosis should avoid taking amphetamines as they are usually much more sensitive to getting psychotic side-effects, and could trigger a relapse of schizophrenia or psychosis.


Mixing amphetamine with other drugs

Taking amphetamine with other stimulants such as MDMA 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).


How addictive is amphetamine?

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. 


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.


Amphetamine harm reduction advice

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.

Injecting drugs tends to be much more harmful

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. 

Tolerance is a warning sign

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.


Last updated 10/10/2012