Impact of Opioids Over Short Periods
Opioid addiction is a complex and challenging brain disorder that arises from long-term use of these powerful prescription medications. The risk of addiction increases significantly when a person takes opioids for an extended period.
Opioids, such as morphine and codeine, bind to opioid receptors in the brain, blocking pain signals and triggering the release of dopamine. This dopamine release can lead to feelings of euphoria and reinforce the desire to take opioids.
Long-term opioid use leads to several neurological changes in the brain. Chronic opioid use increases the expression of the gene transcription factor ΔFosB in the nucleus accumbens, a brain region critical for reward. This sensitizes the reward system and amplifies compulsive opioid seeking. Opioids also inhibit GABAergic neurons in the ventral tegmental area (VTA), leading to increased dopamine release in the nucleus accumbens, which produces euphoria and reinforces drug use.
These changes contribute directly to the development of addiction by altering the brain's natural reward system and reinforcing compulsive drug-seeking behavior. Functional and structural alterations also occur in the orbitofrontal cortex (OFC), essential for controlling reward-related behavior, emotional responses, and anxiety regulation. These brain circuit dysregulations contribute to high impulsivity and difficulty managing emotions and stress, further driving addiction.
Long-term opioid use leads to tolerance (needing higher doses for the same effect) and physical dependence, where the body adapts and experiences withdrawal symptoms upon cessation. However, addiction involves behavioral changes such as loss of control over use and continued use despite harmful consequences. The brain starts relying on opioids to produce positive feelings, weakening the natural reward system so that individuals lose interest in other activities and prioritize drug use, making quitting difficult without professional help.
Genetic factors also contribute to addiction risk, as variations in dopamine receptor genes can affect susceptibility to opioid addiction through differences in dopamine signaling.
In summary, opioid addiction arises because long-term opioid use alters brain reward circuits, disrupts decision-making, emotion regulation, and impulse control, leads to tolerance and physical dependence, weakens the brain’s natural reward system, causing behavioral compulsions to continue use despite negative consequences, and is influenced by genetic susceptibility affecting dopamine receptors. These neurobiological and behavioral changes combined explain why opioid addiction is a chronic, relapsing brain disorder that is challenging to overcome alone.
Help is available for addiction from organizations such as the Substance Abuse and Mental Health Services Administration (SAMHSA) and the 988 Suicide & Crisis Lifeline. In the event of an opioid overdose, it is crucial to seek emergency medical attention immediately. Naloxone, available under the brand name Narcan, is a medication to reverse an opioid overdose by binding to opioid receptors in the brain and blocking the effects of opioids currently in the system.
It's important to note that long-term effects of opioids may vary and can include physical dependence, tolerance, and addiction. Other signs of opioid overdose include falling asleep or losing consciousness, shallow breathing or gasping for breath, choking or gurgling sounds, vomiting, being motionless or still, being pale or having cold skin, a faint or weak pulse. Long-term consequences of snorting or injecting opioids such as heroin include collapsed veins, damages to the tissue inside the nose, heart infections, abscesses.
Opioids are powerful prescription medications used to treat pain, including postsurgical pain, pain from traumatic injury, chronic pain, coughs, and diarrhea. Opioids attach to opioid receptors on nerve cells found in the brain, spinal cord, gut, and other parts of the body, blocking pain messages the body sends through the spinal cord up to the brain.
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