Addiction and Substance Use Disorder (SUD) are often used interchangeably but differ in meaning. Addiction is a chronic condition marked by compulsive substance use or behaviors, like gambling, despite adverse consequences, and includes psychological and physical dependence. SUD refers explicitly to a problematic pattern of substance use (e.g., alcohol, drugs) that causes significant impairment or distress. This covers both legal (e.g., alcohol, nicotine) and illegal substances (e.g., heroin, cocaine). Addiction medicine seeks to treat addictions or substance use disorders (SUD) via medically supervised withdrawal or other means.
Related: Addiction Medicine: Part 1: Opioids and Other Scheduled Drug Classes
Causes of addiction
Addiction is a complex brain disorder influenced by genetic, environmental, social, and psychological factors:
- Genetic vulnerability: A family history of addiction can increase risk due to genetic predispositions that affect substance metabolism and brain response.
- Environmental stressors: Trauma, abuse, economic hardship, and environments where substance use is normalized can raise the likelihood of addiction.
- Social pressures: Peer pressure and cultural acceptance of substance use can encourage experimentation. This can lead to addiction.
- Personality traits: Traits like impulsivity, risk-taking, and a need for novelty are linked to a higher risk of addiction.
- Psychiatric conditions: Mental health issues, such as depression or PTSD, often co-occur with addiction. Individuals may use substances to self-medicate, creating a vicious cycle.
Addiction usually results from a combination of these factors, varying greatly from person to person.
Diagnosis of substance use disorders (SUD)
The diagnosis of SUD relies on identifying these behavioral, physical, and psychological signs and symptoms. Medical professionals often use diagnostic tools, such as the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). The DSM-5 outlines specific criteria for substance use disorders based on the type of substance used, frequency, and severity of use. Laboratory tests may be needed to detect body substances and evaluate related health problems.
The key signs and symptoms that can help diagnose substance use disorders include:
- Behavioral signs: Using larger amounts over time, cravings, failed attempts to cut down, excessive time spent obtaining or using substances. Other signs include engaging in risky behaviors.
- Interference with daily life: Neglecting responsibilities, continued use despite relationship issues, and reduced social or recreational activities.
- Physical and psychological symptoms: Tolerance, withdrawal symptoms, weight loss, fatigue, poor hygiene, and psychological issues like depression, anxiety, or sleep problems.
Risk factors of Opioid Use Disorder
Opioid Use Disorder (OUD) is a condition involving problematic opioid use that leads to significant impairment or distress. Symptoms include unsuccessful attempts to reduce use, lack of control, social impairment, tolerance, and withdrawal. Understanding the risk factors of OUD is crucial for healthcare professionals, especially in critical care settings, due to the rising rates of OUD and its public health impact. The major risk factors of opioid use disorder are:
- Family and personal history: A family history of substance use disorders (SUD) increases the risk of OUD due to genetic and environmental factors. The patient’s personal history of any SUD is also a strong predictor.
- Mental health conditions: Disorders such as psychotic, somatoform, and personality disorders are linked to a higher risk of OUD. This is often due to self-medication with opioids.
- Prescription opioid use: Risk increases with prescriptions lasting over 30 days, daily doses above 120 morphine milligram equivalents (MME), multiple prescribers, and pharmacies. Concurrent use of atypical antipsychotics also raises the risk due to increased sedation and respiratory depression.
Assessing a patient with Opioid Use Disorder
Assessing a patient with opioid use disorder (OUD) involves using clinical judgment, risk assessment tools, and monitoring strategies. This helps identify those at risk, ensures safe opioid use, and provides appropriate interventions.
Key risk assessment tools for OUD
- Opioid Risk Tool (ORT-OUD): A 9-item self-report tool to predict the risk of developing OUD in patients on long-term opioid therapy. A score of 3 or higher indicates risk, with high sensitivity (85.4%) and specificity (85.1%).
- Screener and Opioid Assessment for Patients with Pain (SOAPP): A 24-item self-report questionnaire that predicts the risk of aberrant drug-related behaviors, with a sensitivity of 81% and specificity of 68%.
- Diagnosis, Intractability, Risk, and Efficacy (DIRE) Score: A clinician-rated tool assessing suitability for long-term opioid therapy, with high reliability and validity (sensitivity 94%, specificity 87%).
- Opioid Compliance Checklist (OCC): An 8-item self-report tool to monitor ongoing compliance with opioid therapy, with moderate sensitivity (59.7%) and specificity (65.3%).
Monitoring strategies for opioid use
- Prescription Drug Monitoring Programs (PDMPs): State-run databases track prescriptions to identify potential misuse, such as obtaining opioids from multiple prescribers.
- Urine Drug Toxicology Screening: Tests for the presence of prescribed and non-prescribed substances, with immunoassays for quick results and GC-MS for accuracy.
Pharmacologic management of Opioid Use Disorder
Pharmacologic management of OUD primarily involves two strategies: medically supervised withdrawal and medication-assisted treatment (MAT).
Medically supervised withdrawal
Medically supervised withdrawal, or detoxification, safely manages withdrawal symptoms during the reduction or cessation of opioid use. This provides a safe environment for transitioning away from dependence. However, detox alone is insufficient for long-term recovery due to a high risk of relapse, making medication-assisted treatment (MAT) essential.
Lofexidine, a non-opioid α2-adrenergic agonist approved by the FDA, helps manage withdrawal symptoms like anxiety and agitation by reducing sympathetic activity. While useful for acute withdrawal, opioid agonists and partial agonists, such as methadone and buprenorphine, are more effective for long-term management and relapse prevention.
Medication-Assisted Treatment (MAT)
Medication-assisted treatment (MAT) combines medications with counseling and behavioral therapies to improve treatment retention, reduce illicit opioid use, prevent HIV, and lower mortality. The FDA-approved medications for MAT include methadone, buprenorphine, and naltrexone.
- Methadone: Methadone is a full opioid agonist that reduces withdrawal symptoms, cravings, and the euphoric effects of opioids. It is effective in reducing illicit opioid use and mortality when patients remain in treatment. Methadone is administered in federally licensed opioid treatment programs (OTPs) with a typical maintenance dose of 60-100mg/day. Side effects include nausea, vomiting, constipation, respiratory depression, decreased libido, cognitive impairment, and QT prolongation.
- Buprenorphine: Buprenorphine is a partial opioid agonist with a lower risk of overdose and abuse. It is effective in reducing opioid use, though with slightly lower retention rates than methadone. Available in various forms, it can be prescribed by qualified healthcare providers outside OTPs, expanding access to treatment. Maintenance doses range from 8-24mg/day. Common side effects include dry mouth, nausea, constipation, dizziness, and sedation.
- Naltrexone: Naltrexone is an opioid antagonist that blocks opioid effects and prevents relapse. Extended-release formulations (XR-NTX) improve adherence compared to oral forms. It is administered monthly but requires patients to be opioid-free for 7-10 days to avoid withdrawal. Common side effects include insomnia, nausea, headache, and injection site pain.
Role of pharmacists in OUD management
Pharmacists play a critical role in managing OUD by providing education on MAT options, monitoring medication adherence, managing side effects, and collaborating with healthcare providers to ensure comprehensive care. They are often the most accessible healthcare providers and can offer valuable support in optimizing therapy and improving patient outcomes.
Pharmacists can also help identify patients at risk of opioid overdose and provide naloxone, an opioid antagonist that rapidly reverses opioid overdose. By participating in harm reduction strategies and promoting safe medication use, pharmacists significantly contribute to the public health response to the opioid epidemic.
Naloxone in opioid overdose management
Opioid overdose is a major public health issue due to increased misuse of prescription opioids and illicit drugs like heroin and fentanyl. Naloxone is a critical, life-saving medication that rapidly reverses an opioid overdose by binding to opioid receptors and restoring normal breathing. It is effective only when opioids are present and does not treat opioid use disorder.
Signs of an opioid overdose
Recognizing the signs of an opioid overdose is critical to providing timely intervention. Some common signs include:
- Unconsciousness or inability to wake up
- Very small “pinpoint” pupils
- Slow or shallow breathing
- Vomiting
- Inability to speak
- Faint heartbeat
- Limp arms and legs
- Pale or clammy skin
- Purple or blue lips and fingernails
How is naloxone administered?
Naloxone can be administered in two main ways: as an injectable solution or as a nasal spray.
- Injectable naloxone: Injectable naloxone can be injected into the muscle, under the skin, or directly into the veins. The FDA has recently approved a single-dose, prefilled syringe (Zimhi) that can be injected into the muscle or under the skin.
- Prepackaged nasal spray: The spray, which is available as generic naloxone, Narcan, or Kloxxado, is a needle-free, prefilled device that is sprayed into one nostril while the person lays on their back. This method is often easier for caregivers and bystanders without formal training.
It is important to note that regardless of the delivery method, naloxone training is essential to ensure correct usage. Always read the product instructions and check the expiration date of the device.
Counseling tips for responding to an opioid overdose
When discussing opioid overdose response with patients or caregivers, the following tips should be emphasized:
- Be prepared: Keep naloxone readily available and know where it is stored.
- Understand the signs: Recognize symptoms of an overdose, such as unconsciousness, slow breathing, and pinpoint pupils.
- Know how to administer naloxone: Know how to use naloxone, whether injectable or nasal spray. Practice its use.
- Call 911 immediately: Contact emergency services after administering naloxone, as additional medical attention may be needed.
- Monitor and support: Watch the person closely for returning symptoms and be ready to administer another naloxone dose if needed.
- Be aware of withdrawal symptoms: Be prepared for withdrawal symptoms after naloxone administration, though the risk of overdose death is greater.
- Seek further treatment: Connect the individual to treatment options like medication-assisted treatment and counseling to address opioid use disorder.
Stimulant Use Disorder
Stimulant use disorder is a major public health issue, especially in areas with limited care access. Common stimulants include cocaine, methamphetamine, and prescription stimulants like amphetamines. These drugs stimulate the central nervous system, causing increased alertness and euphoria. They’re linked to addiction, cardiovascular problems, and mental health issues.
Assessment
A thorough assessment is crucial for effective treatment. This includes evaluating substance use patterns, co-occurring mental health disorders, and any other substance use. An individualized treatment plan should address both stimulant use and related health or social issues.
Withdrawal symptoms
Withdrawal symptoms can vary from mild to severe, including:
- Depressed mood
- Low energy
- Irritability
- Increased appetite
- Cravings
Severe cases may involve psychosis or suicidal thoughts. Symptoms typically start within 24 hours of last use and can last 3-5 days, with some lingering effects lasting up to two months. Management involves supportive care and symptom relief.
Treatment approaches
Behavioral therapies, especially cognitive behavioral therapy (CBT) and contingency management (CM) are effective for treating stimulant use disorder. The Matrix Model, which combines therapy, relapse prevention, and peer support, is also effective. While no FDA-approved medications specifically target stimulant use disorder, drugs like mirtazapine and bupropion may help. A comprehensive, individualized approach is essential, including harm reduction and supportive therapy.
Benzodiazepine use disorder
Benzodiazepines (“benzos”) treat anxiety and insomnia by calming the central nervous system but are highly addictive. Benzodiazepine use disorder is characterized by compulsive use despite adverse effects.
Assessment
Assess benzodiazepine use disorder by examining drug use patterns, signs of dependency, and associated health risks. Indicators include taking higher doses than prescribed, obsession with the drug, and impaired daily functioning. Physical and psychological dependence may lead to withdrawal symptoms if use is reduced or stopped abruptly.
Withdrawal symptoms
Withdrawal can be severe, especially with long-term or high-dose use. Symptoms range from mild anxiety and insomnia to severe confusion, hallucinations, and seizures. Symptoms may start within hours to weeks after the last dose. Medical supervision is crucial to manage risks, including seizures.
Treatment
Effective treatment involves a gradual dose reduction under medical supervision to ease withdrawal symptoms and prevent complications. Depending on severity, this can be done in a hospital, treatment facility, or at home. Post-detoxification, ongoing support from healthcare professionals and community resources is essential for relapse prevention. While no specific medications are approved for benzodiazepine use disorder, therapy, and psychological support are crucial for managing addiction.
