What is cocaine?

Cocaine is a drug manufactured from the leaves of the South American shrub Erythroxylon coca (known as coca leaves). 

It's a highly addictive stimulant drug that produces an intense but short-lived sense of euphoria. It comes in several forms. Most is sold as a fine white powder that is usually snorted into the nose, but which can also be dissolved in water and injected. When cocaine is snorted, it is usually divided into lines of powder on a smooth surface and inhaled through a straw or rolled up piece of paper.

Some forms of cocaine, such as freebase cocaine or crack cocaine - which comes as large crystals or lumps about the size of a raisin - are smoked.

Powder cocaine is also known as coke, blow, charlie, c and snow. Crack cocaine may be called rocks, stones or base.

As with other drugs, the purity of cocaine bought on the street is highly variable. Much cocaine has been mixed with other substances such as sugar or starch, so that the seller can make more money from it. 

Cocaine and crack cocaine are Class A illegal substances, with severe penalties for possession or supply. 

Effects of cocaine

When freebase or crack cocaine is smoked, it takes just a matter of seconds for the active chemical to enter the bloodstream in the lungs and travel directly to the brain. It therefore takes effect very quickly and is particularly addictive. 

When cocaine is snorted, the effect is much slower as the chemical first passes through the bloodstream from the nose, into the liver (where it may be partly broken down) and then around the body to the brain.

The effects include:

• Intense sense of euphoria
• Sense of being wide-awake and full of energy
• Enhanced sense of confidence

The physical effects of cocaine include:

• Raised heart rate and blood pressure
• Increased body temperature
• Loss of appetite

The effects are relatively short-lived. For example, the effects of smoking crack last about 10 minutes, while cocaine snorted through the nose lasts up to about 30 minutes. 

As the effects wear off, the person typically experiences low moods and a sense of feeling generally unwell. This can drive them to take more cocaine.

Risks of cocaine

In the short-term, people may act irresponsibly or overconfidently, and may take risks or have accidents as a result of careless behaviour. 

With regular use anxiety, panic attacks and even frank paranoia are common. There may be long-term changes to the brain of users, particularly in the brain's 'reward' circuits, which control sense of pleasure, and personality changes. 

The physical effects of cocaine, especially on the cardiovascular system, increase the risk of problems such as:

• Heart attacks
• Stroke
• Seizures and respiratory problems
• Loss of libido
• Feeling constantly run-down when not taking cocaine

If a woman takes cocaine during pregnancy, there is an increased risk of miscarriage, premature labour and low birth weight. 

When it's regularly snorted, there may be damage to the nasal septum as the drug causes vasoconstriction, clamping down the blood supply to the tissues of the nose. If cocaine is smoked there may be damage to the lungs, while injecting cocaine can damage the veins and lead to ulcers and gangrene, and increases the risk of blood-borne infections such as hepatitis or HIV. 

Cocaine is very addictive and many users quickly develop a strong psychological dependence on it, feeling that they need it just to feel normal. Tolerance may also rapidly develop - this means a person will need increasing amounts of the drug to get the same effect. 

As the effects of cocaine are so short-lived, it doesn't tend to have physical withdrawal effects in the way other drugs do. There are physical effects at the end of a binge as the body 'detoxes' itself fairly quickly – the crash starts almost immediately the cocaine wears off, with fatigue, lack of pleasure, anxiety, irritability, sleepiness and sometimes agitation or extreme suspicion. 

There is also a strong craving for more cocaine. It is this psychological symptom, as well as depression anxiety and irritability, which are the main withdrawal symptoms that persist in the longer term after a binge. 

Management of cocaine addiction

Most people with a significant cocaine habit will need helped from trained professionals to stop using the drug. 

Treatment is mostly aimed at decreasing cocaine use and preventing relapse. Cognitive behavioural therapy, which involves helping a person understand all about their habit (why they use cocaine and what effect it has on them) and how they might change their behaviour, is widely used and has been shown to be effective. Social support in a variety of forms is also important. 

New medications that reduce the severe craving associated with cocaine addiction, as well as treatments aimed at the sort of things which tend to trigger a relapse (such as stress), can also be very helpful. Some people have significant underlying depression that may need treatment. 

Researchers are working on a vaccine against cocaine, which would prevent it from reaching the brain and so block any effect from it. However, this is still in development and not without problems.