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How substance abuse affects your brain

Addiction affects the brain in many different ways, fundamentally changing its structure and functioning. Here’s what you need to know:

How drugs affect the brain

Whether you ingest, inhale, smoke or inject drugs into your system, they change the communication network and disrupt the normal way in which the human brain sends, receives and processes messages. Drugs are chemicals, and when they react with the chemicals that occur naturally in the brain, they have a very powerful effect. There are two key ways drugs work on the brain:

  • Imitating the brain’s natural chemical messages
  • Overstimulating the brain’s reward system

Each drug affects the brain differently. Marijuana (dagga) and heroin, for example, have a chemical structure that mimics a naturally occurring neurotransmitter (a chemical messenger that transmits messages across nerves in the brain). The brain locks onto these ‘imposters’ and activates the nerve cells to transmit messages, but this creates confusion and, over time, the brain malfunctions.

Cocaine and methamphetamine cause the brain to be flooded with dopamine – a chemical often associated with feelings of pleasure and euphoria. 

The reward system

Nicotine, alcohol, cocaine and many other drugs directly affect the brain’s reward centre. When an individual experiences pleasure or happiness, the brain releases dopamine. This creates a compulsion to repeat those experiences. Drugs can hijack this system by releasing large amounts of dopamine and encouraging the brain to repeat those pleasurable experiences. Dopamine in the brain doesn’t cause the high but reinforces the need to repeat the behaviour that causes that feel-good emotion.

How does addiction happen?

Addiction is not a lifestyle choice. It’s a chronic brain disease that can result in irreparable harm and, in extreme cases, fatality. When the chemical structure of the brain is altered, and the individual can’t stop using the drugs that give them pleasure – despite harm and a desire to stop – the individual becomes addicted. This affects their health and wellbeing as well as their quality of life.

It’s also important to note that once brain function has been altered and neural pathways have been rewired, there is a chance that the brain anatomy remains forever affected –  even if the individual stops taking the drugs.

While most people associate addiction with illegal recreational drugs, over-the-counter medication, cigarettes, alcohol and opioids, which include pain-relief medication that is available legally with a prescription, are also addictive. Persons may also become addicted to exercise and food.

The opioid crisis

Opioid addiction has reached crisis proportions across the world, since these pain medications are prescribed often, even though they could lead to addiction if they are used for a prolonged period of time. Always check the side effects of prescribed medication, and if there is a risk of addiction, discuss other options with your doctor. Children and adolescents are at greater risk of addiction, so make sure there’s no other option and that they take the medication for the shortest period possible. 

Life Healthcare is a leading provider of private psychiatric services in South Africa, offering acute mental healthcare in a caring environment in nine facilities across the country.

The information is shared on condition that readers will make their own determination, including seeking advice from a healthcare professional. E&OE. Life Healthcare Group Ltd does not accept any responsibility for any loss or damage suffered by the reader as a result of the information provided.