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Help with “charlie”

9 October 2011 One Comment
No such help for cocaine addicts.....
No such help for cocaine addicts…..

There really is no upside to heroin addiction, but if you were hell bent on finding one then I guess you need look no further than methadone.  Methadone works in much the same way as heroin. It is an agonist, it binds with receptors in the brain the same way that heroin does.  The effect of methadone is more drawn out than it is with heroin.  It is used to wean addicts off heroin by taking its place when an addict stops using.  It doesn’t give a high, but it does prevent the crash-and-burn that is withdrawal, and this gives addicts an opportunity to gain some control over their lives as they struggle with their habit.

Unfortunately for those people that are addicted to cocaine or amphetamines there is no methadone equivalent. For cocaine there are no physical withdrawal symptoms, rather users develop a psychological dependence on the drug.  The fight against addiction can be helped with counselling techniques such as cognitive behaviour therapy, but there are no medications to offer support in the way that methadone  does for heroin addiction.

Researchers at Cambridge University, in the UK, think that they may have found a potential solution to this problem, and the key could rely on drugs that increase the levels of dopamine in the brain.

Dopamine - help may be at hand.
Dopamine – help may be at hand.

Dopamine is a neurotransmitter and is instrumental in influencing behaviour through the brain reward system.  It is the treat that we give ourselves when we do the right thing, and this encourages us to do the same things again.  It also plays a role in learning new behaviours.  For instance, when eating a new type of food, which turns out to be surprisingly nice, our brains produce extra dopamine which produces a feeling of pleasure.  This feeling is then associated with that type of food as we have a positive reinforcement of our behaviour.  This way we learn that this type of food is indeed edible, and lovely, and so we will eat some more if given the opportunity in the future.

Dopamine plays the same role in drug addiction.  For example, the use of cocaine leads to an increase of dopamine in the synapse; the gap between nerve cells.  This floods dopamine receptors with dopamine, which is registered as very pleasurable and thereby encourages users to use the drug again.  After a period of repeated use the brain responds to this by producing less dopamine and reducing the number of receptors.  To get the same feeling of pleasure the user must increase the amount of the drug they use.  This is experienced by the user as building up a tolerance to the drug.

What the scientists at Cambridge have found is that the level of dopamine has a marked influence on the decisions that people make.  Their work involved giving volunteers a learning task to do. Some of these volunteers had a drug dependence and some didn’t.  The researchers found a significant difference in behaviour of the two groups when one of the rules of the task was changed.  The group with no drug issues applied the rule change successfully and carried on performing at the same level as before.  The drugs dependent group however had problems adapting to the new rule.  They carried on the task as if no rule change had occurred, and as a result their performance dropped substantially.

Brain scans showed that this odd behaviour was linked to a drop in activity of the brain’s reward system.  This is significant because this inflexibility is similar to that shown by addicts who are aware of the problems their drug taking is causing but still keep on abusing anyway.

The way out of this problem for addicts could be through the use of dopamine.  The researchers found that when the drug users were given medication to boost the levels of dopamine, the brain reward system began to behave normally and their performance returned to its previous level.

This work shows that dopamine may well hold the key needed to release addicts from their torment.  There is still further work to be done before a product is available,  and it may not be perfect when it comes, but for anyone struggling with dependency this offers the hope of a very useful tool to help combat their addiction.

See the original article at Possible tool to help cocaine users kick the habit

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