Substance Abuse
Substance Abuse — formally called Substance Use Disorder in DSM-5-TR — is a problematic pattern of substance use leading to clinically significant impairment or distress, with severity ranging from mild to severe. The category covers alcohol, tobacco, cannabis, opioids, stimulants, sedatives, and other psychoactive substances.
Overview
“Substance Abuse” is the lay and historical term for what the DSM-5-TR formally calls Substance Use Disorder (SUD). The DSM-5 (2013) consolidated the previous DSM-IV diagnoses of “Substance Abuse” and “Substance Dependence” into a single diagnosis with severity specifiers (mild, moderate, severe). The DSM-5-TR (2022) maintains this framework. This page covers SUDs broadly; substance-specific information is available on the alcohol, drug, smoking, and other dedicated specialty pages.
Substance Use Disorders affect approximately 20% of Canadian adults at some point in their lifetime (any substance). Past-year SUD prevalence is approximately 5-7% for alcohol, 1-3% for cannabis, and 1-2% for other drugs. Tobacco use disorder affects approximately 10-15% of adults. Polysubstance use is common; co-occurring SUDs across substances are the rule rather than the exception in clinical populations.
SUDs are recognized as chronic, relapsing brain disorders with documented neurobiological changes in reward, motivation, executive control, and stress regulation circuits. The “chronic disease” model (comparable to type 2 diabetes or hypertension) is the contemporary clinical framework. This model is associated with reduced stigma, improved treatment engagement, and better outcomes.
Comorbidity with mental-health conditions is the rule rather than the exception. Approximately 50-60% of individuals with SUDs have a co-occurring mental-health condition; the same is true in reverse. Mood disorders, anxiety disorders, PTSD, ADHD, and personality disorders are most common. Trauma history is over-represented across the SUD population.
Treatment is highly effective for most who engage. Combinations of pharmacotherapy (where available), psychotherapy, peer support, harm-reduction services, and treatment of comorbid mental-health conditions produce meaningful improvement. Recovery is typical with sustained treatment, though relapse is common and frequently part of the recovery process.
Signs and symptoms
- Loss of control over use — Use of the substance in larger amounts or over a longer period than intended; repeated unsuccessful efforts to cut down or stop.
- Significant time on substance-related activities — Substantial time obtaining, using, or recovering from the substance.
- Craving — Persistent strong desire or urge to use the substance.
- Failure to fulfill obligations — Recurrent use resulting in failure to fulfill major obligations at work, school, or home.
- Continued use despite social or interpersonal problems — Continued use despite persistent social or interpersonal problems caused or exacerbated by use.
- Important activities given up — Important social, occupational, or recreational activities given up or reduced because of use.
- Use in physically hazardous situations — Recurrent use in situations in which it is physically hazardous.
- Continued use despite physical or psychological harm — Continued use despite knowledge of having a persistent or recurrent physical or psychological problem caused or exacerbated by the substance.
- Tolerance — Need for markedly increased amounts to achieve effect, or markedly diminished effect with same amount.
- Withdrawal — Substance-specific withdrawal syndrome on cessation, or use of the substance to relieve or avoid withdrawal.
Diagnostic context
The DSM-5-TR criteria for any Substance Use Disorder require a problematic pattern of substance use leading to clinically significant impairment or distress, as manifested by at least 2 of 11 criteria within a 12-month period. The 11 criteria fall into four clusters:
Impaired control:
- Use in larger amounts or over longer period than intended.
- Persistent desire or unsuccessful efforts to cut down or control use.
- Significant time spent obtaining, using, or recovering.
- Craving.
Social impairment:
- Recurrent use resulting in failure to fulfill major role obligations.
- Continued use despite persistent social or interpersonal problems.
- Important social, occupational, or recreational activities given up or reduced.
Risky use:
- Recurrent use in physically hazardous situations.
- Continued use despite knowledge of physical or psychological harm.
Pharmacological:
- Tolerance.
- Withdrawal.
Severity: mild (2-3 criteria), moderate (4-5), severe (6+). The framework applies across alcohol, cannabis, hallucinogens, inhalants, opioids, sedative-hypnotics, stimulants, tobacco, and other substances, with substance-specific clinical considerations.
Differential diagnosis includes substance-induced mental disorders (mood, anxiety, psychotic), primary mental disorders with secondary substance use, medical conditions (delirium, dementia, endocrine), and adolescent normative experimentation that does not meet diagnostic threshold. Validated assessment instruments include the AUDIT, DAST, ASSIST, CRAFFT (adolescent), and DSM-5 Adult Self-Rated Substance Use Disorder Symptom Checklist.
Causes and risk factors
SUDs develop through interaction of biological, psychological, and social factors that are largely consistent across substances:
Genetic factors: heritability of SUDs ranges from approximately 40% to 60% across substances. Genetic vulnerability overlaps substantially across substance classes (“general addiction vulnerability”) and with comorbid mental-health conditions.
Neurobiological factors: repeated substance use produces neuroplastic changes in mesolimbic dopamine reward circuits, prefrontal executive control, amygdala stress response, and habenula aversion circuits. These changes persist after acute use ends and contribute to vulnerability to relapse.
Developmental factors: early initiation (before age 15) substantially elevates lifetime SUD risk. Childhood ACE exposure, family history of SUD, ADHD, conduct disorder, and early peer use are all robust predictors.
Psychological factors: co-occurring mental-health conditions (depression, anxiety, PTSD, ADHD, personality disorders) substantially elevate risk and complicate treatment. Trauma history is particularly important; trauma-informed care is essential.
Social and environmental factors: peer use, family use, accessibility, neighbourhood disorder, poverty, discrimination, housing instability, and trauma exposure all contribute.
Substance-specific factors: route of administration (intravenous and inhaled produce higher addictive potential), pharmacokinetics (rapid-onset substances are more addictive), accessibility, social acceptability, and supply contamination (fentanyl in opioids, methamphetamine in stimulants) all affect risk.
Comorbidity: approximately 50-60% of SUD has comorbid mental-health condition. Co-occurring tobacco use disorder is extremely common (>70% in many SUD populations). Co-occurring SUDs across substances are also common.
Typical treatments
Evidence-based treatment combines pharmacotherapy (where available), psychotherapy, peer support, and harm-reduction:
Pharmacotherapy / Medication-Assisted Treatment:
- Alcohol: naltrexone, acamprosate, disulfiram.
- Opioids: methadone, buprenorphine, extended-release naltrexone.
- Tobacco: nicotine replacement, varenicline, bupropion.
- Other substances: limited or no FDA-approved medications.
Psychotherapy: CBT, motivational interviewing, contingency management, mindfulness-based relapse prevention, behavioural couples therapy, trauma-focused therapies for co-occurring PTSD.
Peer support: 12-step programs (AA, NA, others), SMART Recovery, Refuge Recovery, LifeRing. Sustained engagement is associated with better outcomes.
Levels of care: outpatient, intensive outpatient, partial hospitalization, residential, medical detoxification. Matched to severity using ASAM criteria.
Harm reduction: naloxone, supervised consumption, syringe services, drug-checking. Reduces mortality and morbidity for individuals not yet engaging in abstinence-oriented treatment.
Integrated dual-diagnosis treatment for co-occurring mental-health conditions — produces better outcomes than sequential or parallel care.
Treatment of comorbid SUDs: co-occurring tobacco use is extremely common and warrants attention; concurrent treatment improves overall outcomes. Polysubstance use requires comprehensive treatment planning.
Recovery support services: recovery housing, employment services, peer recovery coaches, and family support programs all support sustained recovery.
When to seek help
Professional support is indicated when:
- You have been unable to control substance use despite repeated efforts.
- Use is producing significant consequences in relationships, work, finances, health, or legal status.
- You experience cravings, tolerance, or withdrawal symptoms.
- You are using to manage emotions, cope with stress, or avoid withdrawal.
- Co-occurring depression, anxiety, PTSD, or other mental-health conditions are present.
- You are concealing use from family, partners, or healthcare providers.
- You are using opioids from illicit sources (high fentanyl-related overdose risk).
- You are physically dependent on alcohol or sedative-hypnotics — these withdrawals can be life-threatening; medical supervision is needed for cessation.
Free 24-hour crisis and addictions support: 1-866-332-2322 (Alberta Health Services Addiction Helpline, 24/7), 1-866-531-2600 (ConnexOntario, 24/7), 1-866-585-0445 (Drug & Alcohol Helpline of Ontario), 9-8-8 (Suicide Crisis Helpline), 1-833-456-4566 (Talk Suicide Canada). For Indigenous-led culturally-competent crisis support: 1-855-242-3310 (Hope for Wellness Helpline, 24/7).
Frequently asked questions
Is "substance abuse" the same as substance use disorder?
Can I be treated for SUD without going to rehab?
Is medication-assisted treatment effective?
Do I have to be abstinent to start treatment?
How do I help a family member with SUD?
Is recovery possible?
References
- American Psychiatric Association. (2022). Diagnostic and Statistical Manual of Mental Disorders (5th ed., text rev.). APA.
- Substance Abuse and Mental Health Services Administration (SAMHSA). (2020). Key substance use and mental health indicators in the United States.
- American Society of Addiction Medicine. (2019). The ASAM Criteria: Treatment Criteria for Addictive, Substance-Related, and Co-Occurring Conditions (3rd ed.).
- Volkow, N. D., Koob, G. F., & McLellan, A. T. (2016). Neurobiologic advances from the brain disease model of addiction. New England Journal of Medicine, 374(4), 363–371.
- Canadian Centre on Substance Use and Addiction. (2023). Annual Reports.
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ShiftGrit Psychology & Counselling is professionally regulated, certified, and recognized by leading psychology and mental-health organizations across Alberta and Canada. These associations reflect our commitment to ethical practice, clinical standards, and evidence-informed therapy through Identity-Level Therapy and Reconditioning.
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