In order to understand what causes drug or alcohol addiction, it helps to understand what addiction actually is. There are a lot of misconceptions about addiction but the National Institute on Drug Abuse says:
While some people may suffer from behavioural addictions such as gambling addiction, addictions to drugs and alcohol come about as a result of using an addictive substance. An addiction usually develops gradually over time, but there are instances of people becoming ‘hooked’ on a substance very soon after first using it.
Anyone can develop an alcohol or drug addiction, but there are numerous factors that can increase an individual’s risk of developing an addiction and contribute to the root causes behind their substance misuse.
Effects of the Drug on the Body and Brain
Most drugs that people get addicted to – including legal drugs like alcohol and nicotine and prescription drugs – produce an effect that the person finds enjoyable or desirable. In particular, it will release the neurotransmitter dopamine, often known as the ‘feel good’ chemical of the brain.
Many people will want to replicate this feeling with repeated use but can end up developing a tolerance for the substance as their system gets used to it and adjusts. This cycle of ‘diminishing returns’ means that you need to use more and more of the drug for the same effect. As your body and brain lose the ability to produce dopamine naturally, you may come to rely on the drug even more.
When your system adapts to a drug that you use regularly, it might also adjust to take the new chemical balance into account. This can result in a range of unpleasant and potentially dangerous withdrawal symptoms when the drug is removed. This type of physical dependency can combine with psychological issues and be a major obstacle when people do try to quit or cut down.
Genetic Factors
As our understanding of addiction has improved, numerous studies have shown that genetic factors can increase the risk of some individuals developing a substance misuse issue, up to and including addiction. It has long been known that people growing up in a household where there is alcohol or drug misuse are more likely to develop problems themselves, but the overall picture is often quite complex.
Learned behaviour can certainly play a part but studies involving people in adoptive families show more of a correlation with the natural parents than the adoptive ones. Studies of twins – often used in ‘nature versus nurture’ research – suggest that 45-65% of the liability is due to genetic factors.
Animal studies have also found that rats and mice can be selectively bred for attributes associated with alcohol dependency. A review of existing research in this area concluded that “taken together, there is overwhelming evidence that genetic variations contribute to the risk for alcohol dependence”.
While there appear to be genetic factors contributing to an individual’s risk of developing an addiction, it’s important to note that there is no single ‘addiction gene’.
The study’s authors say: “It is likely that, as for most complex diseases, alcohol dependence and AUDs [alcohol use disorders] are due to variations in hundreds of genes, interacting with different social environments.” They also note that determining which genetic variants have an influence and how they do so is an ongoing area of research.
Environmental Factors
The twin study cited above suggested that anywhere between 45% and 65% of the risk of addiction can be linked to genetic factors. This also means that around half of the cases have no observable genetic links and, even where there are, there may be environmental influences as well.
If problem drinking or drug use is visible in the home, for example, it may well become normalised. If children see people seemingly enjoying themselves (partying etc) they may associate drugs and alcohol with positive feelings and want to experience them at an early age. Even where their experience is overwhelmingly negative – such as where a parent is abusive or substance misuse causes arguments or contributes to divorce – they may still be drawn to drink or drugs themselves, especially if they are unhappy, depressed or anxious. Neglect, boredom and other factors can also increase the risk of substance misuse and eventual addiction.
Environmental influences can extend beyond the family home. Peers and peer pressure can play a huge part in introducing young people to substance misuse of various kinds. This will not always lead to addiction but there is an increased risk when people start experimenting at a younger age.
Mental Health Issues
There are known to be links between substance misuse, addiction and mental health. Many people who are diagnosed with a substance use disorder are also diagnosed with a mental health condition – and vice versa. Research in the US found that more than 60% of adolescents in community-based substance use disorder treatment programs also meet diagnostic criteria for another mental illness.
The relationship between addiction and mental health can be complex, however. In some cases, substance misuse can trigger a mental health episode or worsen an existing condition. In others, people might turn to drugs or alcohol in an attempt to self-medicate because they are already experiencing the symptoms of a mental health condition. This is always counter-productive however and the two elements will tend to feed off each other. Where addiction and mental health conditions co-exist, this is often referred to as dual diagnosis and it is generally advisable to treat both sides at the same time.
There is no one thing that ‘causes’ addiction. Anyone who uses them can become addicted to drugs and alcohol, but there are many different factors that can increase the risk and the true picture is often a complex combination of these different threads. If you feel like you need professional drug or alcohol rehabilitation treatment, you can get in touch with us today.
