Substance Abuse

The United States is currently enduring an opioid crisis. Many individuals are dying from this issue and it’s important to know why.

Drug use significantly affects the neurochemistry of the brain. Our brain has a baseline for what it considers normal. Certain substances can change this baseline and levels of specific neurotransmitters can fluctuate. Different drugs have different effects on your brain. Substances such as cocaine, nicotine, and caffeine are stimulants, which increase central nervous system activity- increased heart rate, respiration, and blood pressure. Others, such as benzodiazepines and alcohol are depressants, which slow down the central nervous system. Drugs like heroin and oxycoton attack a specific neurotransmitter- endorphin (the body’s natural pain killer). These endorphins are received and communicated by opiate receptors, which inhibit (lessen) the feeling of pain throughout the body. When heroin is introduced to the body, it overstimulates the opiate receptors, which heightens this “non-painful” feelings that turns into euphoria. Opiod abuse is highly addictive for this reason.

Opiod receptors inhibit (stop) GABAergic neurons (neurons that lessen the effects of the dopamine). The dopamine system plays a significant role in substance abuse. The release of dopamine (from the nucleus accumbens) creates a surge of pleasure and reward and decreasing stress and anxiety (in the amygdala). This misguides our and tells it, “Hey, this feels good! Opiates are rewarding!” It reinforces the feeling opiates provide. Opiates bombard the brain with dopamine neurotransmitters which helps the user receive a heightened feeling of pleasure, causing them to repeat this behavior over and over again as they chase the euphoric feeling. The prefrontal cortex is also unable to function properly and rationality is distorted.

The neural plasticity of the brain helps to acclimate itself to new environments. This adaptability can be both beneficial and malproductive. Drugs change the brain’s baseline release of neurotransmitters. After extended (sometimes even temporary) use of substances, like opiates, the brain begins to adapt. With opiate use, the brain releases such a substantial amount of endorphins and dopamine, that the person almost feels abnormal without this euphoric feeling. Dopamine and endorphin levels are below average, causing the person to feel uncomfortable and upset. The user can feel negative physical or psychological impacts from terminated use, which is known as withdrawal. This is dangerous because once the user is sober, their tolerance decreases and there is a risk of overdose if drugs are re-introduced to the body.