Substance Use Disorder

Overview

Substance use disorder (SUD) refers to the problematic use of chemicals, including drugs and alcohol, that leads to physical, psychological, or social adverse effects. SUD is a multifactorial condition with significant implications for nutrition, metabolism, and overall health.

• Impaired control: Difficulty limiting substance use.

• Craving: Strong desire to use the substance.

• Social impairment: Disruption of social, occupational, or recreational activities.

• Risky behaviors: Use in hazardous situations.

• Tolerance: Need for increased amounts to achieve the same effect.

• Withdrawal: Physical and psychological symptoms upon cessation.

Pathophysiology

Complex, Multifactorial Process

The development of SUD involves genetic, environmental, and psychological factors. The brain's reward system is altered, leading to compulsive substance seeking and use.

• Kindling: Repeated cycles of intoxication and withdrawal increase the severity of withdrawal symptoms over time.

Kindling Graph: Severity of withdrawal symptoms increases with repeated cycles of alcohol intoxication and withdrawal.

Science of Addiction

Neurobiology of Addiction

Addiction affects several brain regions, including the nucleus accumbens, prefrontal cortex, amygdala, and hippocampus. These areas are involved in reward, decision-making, and memory.

1. Initial use activates the brain's reward system, releasing dopamine and producing pleasure.

2. The hippocampus forms memories of the pleasurable experience, reinforcing future use.

3. Repeated exposure strengthens neural pathways, making the behavior more automatic.

4. Over time, the person loses control and continues use despite negative consequences.

Comparison: Addiction is similar to other chronic diseases in that it is preventable, treatable, and involves changes in biology.

Etiology

Risk Factors

SUD can affect individuals of any age, gender, or socioeconomic status. Risk factors include:

• Family history

• Mental illness

• Peer pressure

• Lack of family involvement

• Male gender

Adolescents are often influenced by peers, while adults may develop SUD due to prescription opioid pain relievers.

Clinical Manifestations

Caffeine

Caffeine is a stimulant consumed daily in various beverages. Excessive intake can lead to withdrawal symptoms and should be avoided in individuals with cardiac disease.

• Adolescents are at risk due to energy drink consumption.

Cannabis

Delta-9-tetrahydrocannabinol (THC) is the main psychoactive component. Cannabis potency has increased, and its use can lead to various effects:

• Increased heart rate

• Bronchodilation

• Enhanced sensory perception

• Euphoria

• Drowsiness/relaxation

• Increased appetite

• Slowed reaction time

• Memory impairment

Central Nervous System Depressants

Includes barbiturates and benzodiazepines. Used for anxiety and sleep disorders but can cause dependence and increase risk of accidental death, especially with alcohol.

• Examples: Zolpidem, Eszopiclone, Diazepam, Lorazepam

Psychostimulants

• Cocaine (Crack): Euphoria, dilated pupils, increased heart rate, insomnia, risk of sudden cardiac arrest.

• Amphetamine: Increased activity, decreased appetite, prescribed for ADHD.

• Methamphetamine: Highly addictive, easy to manufacture, causes psychological dependence.

Opiates

Prescription opioids and heroin are commonly abused. Opiates can cause euphoria, drowsiness, and respiratory depression. Withdrawal symptoms include craving, lacrimation, rhinorrhea, and diarrhea.

Heroin Withdrawal Timeline

• Tachycardia

• Restlessness

• Bone/joint pain

• Diarrhea, vomiting

• Gooseflesh skin

• Diaphoresis

• Dilated pupils

• Runny nose

• Tearing

• Tremor

• Yawning

• Craving

Hallucinogens

• LSD, PCP, Ecstasy, Ketamine, Dextromethorphan

• Altered awareness, hallucinations, dissociation

• Side effects: nausea, vomiting, loss of appetite, impaired movement, sweating, paranoia, weight loss

Inhalants

• Anesthetics, volatile nitrates, organic solvents

• Brain damage risk, mild withdrawal with long-term use

Preventing and Responding to Opioid Overdose

Signs and Symptoms

• Pinpoint pupils

• Loss of consciousness

• Slow, shallow breathing

• Choking/gurgling sounds

• Limp body

• Pale, blue, cold skin

Emergency Response

• Call 911

• Administer naloxone

• Lay person on their side (recovery position)

• Administer second dose after 2-3 minutes if needed

• Stay with person until paramedics arrive

Naloxone (Narcan)

• Opioid antagonist, reverses opioid overdose

• Fast acting, can be administered via shot or nasal spray

• Not to be confused with naltrexone (used for long-term treatment)

Treatment

Multidisciplinary Approach

• Detoxification

• Medications for side effects

• Psychotherapy

• Family counseling

• Self-help groups

Pharmacological Therapy

• Drugs for alcohol use disorder

• Nicotine replacements

• Opioid antagonists (e.g., naloxone)

• Opioid agonist antagonists (e.g., buprenorphine-naloxone)

• Vitamins (to address nutritional deficiencies)

Emergency Care

• Medical emergency: respiratory depression may require ventilation

• Monitor for delirium, psychosis, suicidality

• Suicide precautions may be necessary

• Patient safety is the priority

Lifespan Considerations

• Newborns: Neonatal abstinence syndrome (NAS), neonatal opioid withdrawal syndrome (NOWS)

• Adolescents

• Pregnant women

• Older adults

Nursing Process

• Care and treatment are challenging

• Remain nonjudgemental, promote mutual trust and respect

• Provide information on healthy coping mechanisms

• Education on effects of substances

• Support during abstinence and lifestyle changes

• Health promotion activities

Assessment

• Observation and interview

• History of past substance use

• Medical and psychiatric history

• Psychosocial issues

• Screening tools: Clinical Opiate Withdrawal Scale (COWS), subjective/objective withdrawal scales

• Open-ended questions

Medications for Opioid Use Disorder

Methadone (Methadose, Dolophine)

• Long-acting opioid agonist

• Reduces craving and withdrawal

• Blunts or blocks effects of opioids

• Available in liquid, powder, or diskette form

• Only certified treatment programs can dispense methadone

Side Effects

• Restlessness

• Constipation

• Nausea/vomiting

• Itchy skin

• Slow breathing

• Serious: difficulty breathing, chest pain, tachycardia, hives/rash

Buprenorphine-Naloxone (Suboxone), Buprenorphine (Subutex)

• Partial opioid agonist

• Diminishes withdrawal symptoms and cravings

• Ceiling effect reduces risk of misuse

• Naloxone component discourages injection misuse

Side Effects

• Headache

• Nausea, vomiting

• Constipation

• Insomnia

• Signs and symptoms of withdrawal

• Pain

• Peripheral edema

Nursing Considerations

• Must abstain from opioids for 12-24 hours before starting

• Monitor for respiratory depression

• Do not inject sublingual film; can cause severe withdrawal and health problems

Key Equations

• Pharmacokinetics: (where is concentration, is initial concentration, is elimination rate constant, is time)

• Withdrawal Severity (Kindling): (where is severity after cycles, is initial severity, is increment per cycle)

Additional info:

• Nutrition is impacted by substance use through appetite changes, malnutrition, and vitamin deficiencies, especially in alcohol and opioid use disorders.

• Vitamin supplementation is often necessary in recovery, particularly thiamine for alcohol use disorder.