Amphetamines (speed): what are the effects?
The effects of any drug (including amphetamines) vary from person to person, depending on the individual's size, weight and health, how much is taken and how the drug is taken, whether the person is used to taking it and whether other drugs are taken. It also depends on the environment in which the drug is used — for example, whether the person is alone, with others, or at a party.
Immediate effects
Soon after taking amphetamines, the following effects may be experienced.
- Speeding up of bodily functions. Amphetamines speed up the body's activity. Heart rate, breathing and blood pressure increase. A dry mouth, increased sweating, enlargement of the eye's pupils and headaches may occur.
- More energy and alertness. Users can feel energetic and full of confidence, with a heightened sense of well-being. Other effects include feeling wide awake and alert, becoming talkative, restless, excited, and having difficulty sleeping. Panic attacks may also be experienced.
- Reduced appetite.
- Irritability. Some users become anxious, irritable, hostile and aggressive. Sometimes people feel a sense of power and superiority over others.
Impure amphetamines
Most amphetamines sold illegally contain a mixture of pure amphetamines and other substances such as sugar, glucose, bicarbonate soda, and ephedrine. These additives can be highly poisonous. They can cause collapsed veins, tetanus, abscesses, and damage to the heart, lungs, liver and brain. And because the person doesn't know whether they are using 5 per cent or 50 per cent pure amphetamines, it is easy to overdose by accident.
In greater quantities
Very high quantities of amphetamines can cause paleness, headaches, dizziness, blurred vision, tremors, irregular heartbeat, stomach cramps, sweating, restlessness, irregular breathing and loss of co-ordination. Some users have collapsed after taking amphetamines. High quantities can also create an ‘amphetamine psychosis’ characterised by paranoid delusions, hallucinations and aggressive or violent behaviour.
Effects of overdosing
Due to the unknown strength and mix of street amphetamines, some users have overdosed and experienced strokes, heart failure, seizures and high body temperature. Some have died as a result. Injecting runs a greater risk of overdosing due to large amounts of the drug entering the bloodstream and quickly travelling to the brain.
Coming down
As the effects of amphetamine begin to wear off, a person may experience a range of symptoms including uncontrolled violence, tension, radical mood swings, depression and total exhaustion.
Long-term effects
Regular use of amphetamines may result in chronic sleeping problems, anxiety and tension, high blood pressure and a rapid and irregular heartbeat. In order to combat these drug-related effects, people who use amphetamines may also use alcohol, benzodiazepines, other sedatives/hypnotics, cannabis and opiates.
Other possible long-term effects
- Malnutrition. Amphetamines reduce appetite, resulting in people being less likely to eat properly.
- Psychosis. Frequent heavy use can cause ‘amphetamine psychosis’. Symptoms may include paranoia as well as delusions, hallucinations and bizarre behaviour. These symptoms usually disappear a few days after the person stops using amphetamines.
- Reduced resistance to infections. Regular amphetamine users often don't eat or sleep properly and are generally run down, so their resistance to infections is reduced.
- Violence. People who use amphetamines regularly or in high quantities may suddenly become violent for no apparent reason.
- Brain damage. There is some evidence that amphetamine use may damage brain cells. This damage can result in reduced memory function and possibly other impairments in thinking.
For more information, please click on the Australian Drug Foundation's DrugInfo Clearinghouse web site link below.
Last Reviewed: 20 September 2006
