Substance use extends beyond its immediate physiological effects, exerting profound influence over cognitive functioning and precipitating significant behavioral changes. These alterations can create a feedback loop that sustains continued substance use, often despite awareness of potentially fatal consequences.
Marin County is no stranger to substance use, ranking in the top 30 counties for opioid overdoses, including prescriptions, heroin, and fentanyl.
At Alta Mira, our team of specialists focuses on substance use disorders and co-occurring mental health conditions. In this report, we’ll explore substance use disorders, including how to identify the characteristics of drug addiction in a loved one.
Drug addiction is a complex and multifaceted disorder that affects millions of individuals worldwide. More commonly known as substance use disorders, drug addiction is characterized by the compulsive use of substances despite harmful consequences. While its external manifestations – such as damaged relationships, declining physical health, and deteriorating mental health – are widely recognized, the root of substance use disorders lies deeply in the brain’s neurobiology. Understanding addiction from a neurological perspective provides valuable insights into why individuals continue their use despite this destructive cycle.
Substance use disorders alter brain chemistry in profound ways, primarily by affecting the brain’s reward system. At the center of this system lies a neurotransmitter called dopamine, which plays a pivotal role in how pleasure and reward are experienced. When a person engages in activities necessary for survival – such as eating or socializing – the brain releases dopamine, reinforcing these behaviors as pleasurable and worth repeating. Substances interrupt this natural process by flooding the brain with excessive amounts of dopamine, producing an exaggerated sense of euphoria.
Repeated substance use causes the brain to adapt by reducing its production of dopamine or diminishing its receptors’ sensitivity. The person will require more of the substance to achieve the same effects, which builds their tolerance to the substance. This neurobiological adaptation contributes to the compulsive nature of substance use disorders and makes it difficult for people to experience pleasure from everyday activities. With these changes, the brain’s prefrontal cortex – which is responsible for decision-making, impulse control, and emotional regulation – also becomes impaired, making it increasingly difficult for the person to exert control over their substance use.
Substance use disorders are a type of mental health condition with distinct characteristics that perpetuate the cycle of continued use. These include tolerance, withdrawal, denial, loss of willpower, and obsession or preoccupation with the substance. Each characteristic plays a specific role in maintaining the addiction and making recovery difficult without proper intervention.
Tolerance is more than just a behavioral mechanism – it can occur on a molecular and biological scale. This is not just limited to illicit substances or alcohol as tolerance can occur from any substance, including over-the-counter and prescription medications. Originally, tolerance was defined as a form of behavioral plasticity as a decreased response to persistent and repeated drug use. Studies have shown that this response is either intrinsic or extrinsic.
Intrinsic tolerance is the result of changing neurons that control behaviors. Extrinsic tolerance is an adaptation, resulting from alterations in compensatory neural circuits. These can be acute or chronic and also in some cases rapid.
Repeated exposure results in chronic tolerance, which is the most commonly seen in substance use disorders. As the brain becomes accustomed to the presence of the substance, it needs more of it to activate the same reward pathways and produce euphoria. This leads the person to escalate their use, increasing the risk of overdose and other serious health complications.
Withdrawal symptoms occur when the person taking substances reduces or discontinues their use. These symptoms are a direct result of continued substance use over a period of time with a sudden decrease or stop of use. Chemical changes within the brain take place with substances – and when use discontinues – the brain is forced to regain equilibrium. This results in withdrawal symptoms as the brain signals a need for continued substance use.
Individual substances result in different forms of withdrawal. For example, opioid withdrawal is uncomfortable but normally does not become life-threatening. Though rare, delirium tremens (DTs) happen during alcohol withdrawal which results in hallucinations, delusions, and seizures. One study highlighted alcohol “kindling,” where the more times a person went through alcohol withdrawal, the more likely they were to experience seizures and DTs.
The physical “unwell” feelings associated with withdrawal are uncomfortable and result in poor mental health. It becomes easier for the person to keep taking substances rather than experience these symptoms.
Denial is a psychological defense mechanism commonly seen in individuals with substance use disorders. It allows them to minimize or outright reject the reality of their situation, despite clear evidence to the contrary. Denial may manifest in several ways, including underestimating the amount of substances consumed, rationalizing the use of substances as a necessary coping mechanism, or shifting blame to external factors such as stress, trauma, or relationships.
A study was conducted at five substance use disorder treatment centers, with participants aiming to explore their understanding of denial in relation to substance use disorders. The research analyzed transcripts and developed models of denial. One part identified key interpersonal and attributional processes explaining why participants failed to recognize or admit their substance use. The other identified five stages of progressing from no awareness to full awareness of the disorder. These models were later combined, revealing that denial is a complex and dynamic process involving both internal and social factors.
Substance use disorder takes away a person’s ability to exert willpower over their substance use. While in the early stages, the person feels a sense of control, but repeated exposure to substances gradually impairs the brain’s executive functions, particularly those governed by the prefrontal cortex. The loss of willpower is not a matter of choice or motivation but rather a consequence of the brain’s altered state.
One study argues that substance use disorder impairs people’s ability to make choices based on long-term outcomes due to an imbalance between two neural systems: the impulsive system (amygdala) focused on immediate pleasure or pain, and the reflective system (prefrontal cortex) focused on future consequences. Normally, the reflective system controls the impulsive system after social learning. However, when the impulsive system becomes hyperactive, it can overpower the reflective system. Drugs can amplify signals from the amygdala, hijacking cognitive resources and weakening the reflective system, making it harder to exercise willpower and resist drug use.
One of the defining features of substance use disorder is the constant obsession or preoccupation with obtaining and using the substance. Those living with a substance use disorder spend an excessive amount of time thinking about their drug of choice, planning how to acquire it, and finding ways to use it. This preoccupation dominates their thoughts, leaving little room for other activities or relationships.
The term “addiction” has historically referred to impaired control over substance use, but recently it’s been applied to non-substance disorders like pathological gambling. A study examined the classification of behavioral addictions by comparing participants with alcohol use disorder, pathological gambling, and compulsive buying disorder. Participants completed several assessments measuring addiction symptoms, impulsivity, and psychological distress. While the alcohol dependence group reported more severe symptoms and higher depression and anxiety, there were broad similarities across the three disorders in cravings, impulsivity, and obsessions. These findings support expanding the definition of addiction to include non-substance-related disorders, potentially improving treatment approaches.
Recognizing the signs of substance use disorder in a loved one is daunting, especially when denial and secrecy are involved. However, there are several behavioral, physical, and psychological symptoms that show indications of substance use and subsequent substance use disorder. These include:
Changes in behavior: Loved ones living with addiction will exhibit changes in their behavior, such as withdrawing from social activities, neglecting responsibilities, or engaging in risky behaviors. They will become secretive about their activities and whereabouts, particularly when it comes to their substance use.
Physical symptoms: Physical signs of substance use vary depending on the substance, but common indicators include weight loss, poor hygiene, bloodshot eyes, scarring or infections of the skin, and facial or physical deformities. This is especially true with intravenous substance use.
Mood swings: Substance use disorder leads to extreme mood swings, ranging from euphoria while under the influence to irritability, anxiety, or depression during withdrawal. Loved ones will notice their once-joyful or stable family member becoming increasingly volatile or emotionally distant.
Financial difficulties: Loved ones living with a substance use disorder find financial difficulties as a result of spending large amounts of money on substances and negative behaviors.
Changes in sleep patterns: Substance use disrupts normal sleep patterns, leading to insomnia or excessive sleeping. Stimulants may cause your loved one to stay awake for extended periods, while depressants may result in prolonged sleep or drowsiness.
Neglecting personal relationships: Substance use disorder causes loved ones to withdraw from friends and family, isolating themselves as their substance use becomes their primary focus. They also experience conflict in relationships due to their erratic behavior or dishonesty.
Substance use disorder is a complex condition characterized by compulsive substance use despite harmful consequences, driven by behavioral, psychological, and physiological dependencies. Neurological changes, genetic predispositions, and environmental factors all contribute to its development.
To properly treat substance use disorder, professionals must adopt a comprehensive, evidence-based approach that includes psychoeducation and accessible treatment options. By addressing both the individual and societal factors, the goal is to reduce stigma and improve recovery outcomes. It’s time to make meaningful changes through coordinated efforts across healthcare, policy, and community initiatives.
If you or someone you love is living with a substance use disorder, help is available right now. Alta Mira backs all addiction treatments with science-based care. Based in the beautiful Sausalito area, we offer a peaceful and serene place to begin your recovery. Call us today at 833-309-0804 to learn more about our program offerings.
Alta Mira: Science-backed treatment, world-class care.
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