Study guide
11.6 Pharmacotherapy for Alcohol & Opioid Use Disorder
ABIM Internal Medicine Exam
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1 Chapter 0: The ABIM Exam, Blueprint & Study Strategy
0.1 Exam Format, Question Types & the 2026 Blueprint 0.2 Eligibility, Registration, Fees & Exam-Day Logistics 0.3 Scoring, the Passing Standard & Score Reports 0.4 Building a Blueprint-Weighted Study Plan
2 Chapter 1: Cardiovascular Disease (14% of Exam)
1.1 Ischemic Heart Disease & Acute Coronary Syndromes 1.2 Antithrombotic Therapy, Secondary Prevention & Mechanical Complications of MI 1.3 Atrial Fibrillation, Atrial Flutter & Stroke Prevention 1.4 Supraventricular Tachycardias, Ventricular Arrhythmias & Bradycardias 1.5 Heart Failure: Classification, Staging & Guideline-Directed Medical Therapy 1.6 Device Therapy, HFpEF & the Cardiomyopathies 1.7 Valvular Heart Disease & Endocarditis Prophylaxis 1.8 Pericardial Disease & Acute Aortic Syndromes 1.9 Hypertension: Classification, Diagnosis & Secondary Causes 1.10 Hypertensive Crises & Dyslipidemia 1.11 Adult Congenital Heart Disease & Coarctation of the Aorta 1.12 Syncope: Reflex, Orthostatic & Cardiac Causes 1.13 Cardiac Physical Examination, Murmurs & Antithrombotic Selection
3 Chapter 2: Endocrinology, Diabetes & Metabolism (9% of Exam)
2.1 Diabetes Mellitus: Diagnosis, Glycemic Targets & Pharmacotherapy 2.2 Insulin Therapy, Hyperglycemic Emergencies & Chronic Complications 2.3 Thyroid Function Testing & Hypothyroidism 2.4 Thyrotoxicosis, Thyroid Storm & Thyroid Nodules 2.5 Adrenal & Pituitary Disorders 2.6 Hypercalcemia, Hypocalcemia & Disorders of Mineral Metabolism 2.7 Osteoporosis & Paget Disease of Bone 2.8 Ovarian, Testicular & Reproductive Endocrine Disorders 2.9 Hypoglycemia, Endocrine Tumors, Polyglandular Syndromes & Severe Hypertriglyceridemia
4 Chapter 3: Gastroenterology & Hepatology (9% of Exam)
3.1 Esophageal Disease 3.2 Stomach & Duodenal Disease and Gastrointestinal Hemorrhage 3.3 Inflammatory Bowel Disease 3.4 Celiac Disease & Irritable Bowel Syndrome 3.5 Diverticular Disease & Colorectal Cancer Screening 3.6 Viral Hepatitis, Steatotic & Alcohol-Associated Liver Disease 3.7 Cirrhosis & the Complications of Portal Hypertension 3.8 Acute Pancreatitis 3.9 Chronic Pancreatitis & Biliary Tract Disease 3.10 Inherited, Autoimmune & Drug-Induced Liver Disease 3.11 Small Intestinal Disease, Ischemia & Gastrointestinal Complications of HIV
5 Chapter 4: Infectious Disease (9% of Exam)
4.1 Lower Respiratory Tract Infections & Sepsis Syndromes 4.2 Viral Respiratory Pathogens & Tuberculosis 4.3 Central Nervous System Infections 4.4 Skin, Soft Tissue, Bone & Joint Infections 4.5 Infective Endocarditis & Cardiovascular Infection 4.6 Clostridioides difficile & Catheter-Related Bloodstream Infection 4.7 HIV Diagnosis, Antiretroviral Therapy & Prevention 4.8 Opportunistic Infections & Sexually Transmitted Infections 4.9 Fever of Unknown Origin, Neutropenic Fever & Toxic Shock 4.10 Travel-Related Illness, Vector-Borne Disease & Outbreaks 4.11 Infection Prevention, Nosocomial Infection & Postexposure Prophylaxis 4.12 Rheumatic Fever, Poststreptococcal Disease, Enteric & Hepatic Infections
6 Chapter 5: Pulmonary Disease (9% of Exam)
5.1 COPD: Diagnosis, GOLD Classification & Initial Pharmacotherapy 5.2 Interventions That Reduce COPD Mortality & Exacerbation Management 5.3 Asthma: Diagnosis, Stepwise Therapy & Status Asthmaticus 5.4 Interstitial Lung Disease & Idiopathic Pulmonary Fibrosis 5.5 Sarcoidosis, Hypersensitivity Pneumonitis & Occupational Lung Disease 5.6 Pulmonary Embolism: Diagnosis, Risk Stratification & Anticoagulation 5.7 Pulmonary Hypertension & Sleep-Disordered Breathing 5.8 Acute Respiratory Distress Syndrome & Mechanical Ventilation 5.9 Pleural Disease, Empyema & Pneumothorax 5.10 Bronchiectasis, Cystic Fibrosis & Restrictive Lung Disease 5.11 Evaluation of Cough, Dyspnea, Hemoptysis & the Solitary Pulmonary Nodule
7 Chapter 6: Rheumatology & Orthopedics (9% of Exam)
6.1 Rheumatoid Arthritis: Diagnosis & Systemic Manifestations 6.2 Antirheumatic Pharmacotherapy & the Spondyloarthropathies 6.3 Gout: Pathophysiology & Acute Management 6.4 Urate-Lowering Therapy & Calcium Pyrophosphate Deposition Disease 6.5 Osteoarthritis 6.6 Systemic Lupus Erythematosus 6.7 Systemic Sclerosis, Sjogren Syndrome & Inflammatory Myopathies 6.8 The Vasculitides 6.9 Regional Musculoskeletal Syndromes, Back Pain & Sports Injuries 6.10 Other Primary Rheumatic Disorders & Mixed Connective Tissue Disease 6.11 Osteonecrosis & Metabolic Bone Disease
8 Chapter 7: Hematology (6% of Exam)
7.1 Approach to Anemia & the Microcytic Anemias 7.2 Macrocytic, Normocytic & Hemolytic Anemias 7.3 Hemoglobinopathies, Thalassemias & Paroxysmal Nocturnal Hemoglobinuria 7.4 Platelet Disorders, Thrombocytopenia & the Bleeding Patient 7.5 Coagulation Factor Disorders, Thrombophilia & Anticoagulant Reversal 7.6 Acute Leukemias, Chronic Leukemias & Myeloproliferative Neoplasms 7.7 Lymphomas & Plasma Cell Disorders 7.8 Myelodysplastic Syndrome, Myeloproliferative Neoplasms & Porphyria 7.9 Transfusion Medicine & Late Complications of Transplantation
9 Chapter 8: Medical Oncology (6% of Exam)
8.1 Breast, Lung, Colorectal & Prostate Cancer 8.2 Oncologic Emergencies 8.3 Genitourinary & Gynecologic Malignancies 8.4 Head and Neck, Bone & Soft Tissue Cancer and Cancer of Unknown Primary 8.5 Complications of Cancer & Its Treatment 8.6 Cancer Prevention, Survivorship & Psychosocial Care
10 Chapter 9: Nephrology & Urology (6% of Exam)
9.1 Acute Kidney Injury: Staging, Etiology & Urine Microscopy 9.2 Glomerular Disorders & Nephrotic Syndrome 9.3 Nephritic Syndromes, RPGN & Indications for Renal Replacement Therapy 9.4 Chronic Kidney Disease: Staging & Progression Retardation 9.5 Complications of Chronic Kidney Disease: Anemia, CKD-MBD & Acidosis 9.6 Hyponatremia, Hypernatremia & Water Balance 9.7 Potassium Disorders & Systematic Acid-Base Analysis 9.8 Renal Tubular Acidosis & Nephrolithiasis 9.9 Prostate Disorders, Urinary Incontinence & Other Urologic Conditions 9.10 Cystic Kidney Disease, Obstructive Uropathy, Tubulointerstitial Disease & Hematuria
11 Chapter 10: Neurology (4% of Exam)
10.1 Acute Ischemic Stroke: Syndromes & Reperfusion 10.2 Transient Ischemic Attack, Secondary Prevention & Hemorrhagic Stroke 10.3 Headache & Facial Pain 10.4 Seizures, Epilepsy & Movement Disorders 10.5 Multiple Sclerosis & Neuromuscular Junction Disorders 10.6 Motor Neuron Disease & Acute Peripheral Neuropathy 10.7 Cranial Neuropathies & Neuro-Ophthalmology 10.8 Peripheral Neuropathies, CNS Tumors & Other Neurologic Disorders
12 Chapter 11: Psychiatry & Behavioral Health (4% of Exam)
11.1 Major Depressive Disorder & Medical Mimics 11.2 Antidepressant Pharmacotherapy & Treatment-Resistant Depression 11.3 Bipolar Disorder, Mood Stabilizers & Lithium Toxicity 11.4 Anxiety, Stress-Related & Obsessive-Compulsive Disorders 11.5 Alcohol Use Disorder & Withdrawal 11.6 Pharmacotherapy for Alcohol & Opioid Use Disorder 11.7 Toxidromes, Psychiatric Emergencies & Suicide Risk Assessment 11.8 Psychotic, Somatic Symptom, Factitious & Personality Disorders 11.9 Eating Disorders, Sleep Disorders & Sexual Health
13 Chapter 12: Dermatology (3% of Exam)
12.1 Dermatitis, Papulosquamous & Inflammatory Dermatoses 12.2 Acne, Rosacea & Cutaneous Infections 12.3 Herpes Zoster & Autoimmune Blistering Diseases 12.4 Nodules, Tumors & Cutaneous Oncology 12.5 Dermatologic Emergencies & Severe Cutaneous Adverse Reactions 12.6 Pigment Disorders, Alopecia, Nail Disease & Photosensitivity 12.7 Vascular Dermatoses, Environmental Injury & Cutaneous Signs of Systemic Disease
14 Chapter 13: Obstetrics & Gynecology / Women's Health (3% of Exam)
13.1 Contraception, Preconception Care & Teratogenicity 13.2 Hypertensive Disorders of Pregnancy & Gestational Diabetes 13.3 Thyroid Disease & Venous Thromboembolism in Pregnancy 13.4 Menopause & Menopausal Hormone Therapy 13.5 Abnormal Uterine Bleeding, Endometrial Disease & Gynecologic Cancer Screening 13.6 Breast Disorders & Diseases of the Vulva and Vagina 13.7 Menstrual Disorders, Fibroids, Endometriosis & Early Pregnancy Complications
15 Chapter 14: Geriatric Syndromes (3% of Exam)
14.1 Comprehensive Geriatric Assessment & Frailty 14.2 Falls, Gait Assessment & Polypharmacy 14.3 Urinary Incontinence & Pressure Injuries in Older Adults 14.4 Mild Cognitive Impairment, Dementia & Its Subtypes 14.5 Delirium & the Pharmacotherapy of Cognitive Disorders 14.6 Palliative Care, Hospice & Advance Care Planning 14.7 Chronic Wounds, Nutrition, Swallowing, Constipation & Hip Fracture 14.8 Sensory Impairment, Dizziness, Elder Mistreatment & Care Settings
16 Chapter 15: Allergy & Immunology (2% of Exam)
15.1 Anaphylaxis: Recognition & Emergency Management 15.2 Urticaria & Angioedema 15.3 Drug Allergy, Desensitization & Adult Immunodeficiency 15.4 Food Allergy, Insect Venom Hypersensitivity, Serum Sickness & Contrast Reactions 15.5 Rhinitis, Conjunctivitis, Eosinophilic & Mast Cell Disorders
17 Chapter 16: Preventive Medicine, Immunization & Clinical Epidemiology
16.1 The USPSTF Framework & Evidence-Based Cancer Screening 16.2 Cardiovascular & Metabolic Screening and Primary Prevention 16.3 Adult Immunization & Vaccines in Special Populations 16.4 Clinical Epidemiology, Biostatistics & Study Design
18 Chapter 17: Miscellaneous - Ethics, Patient Safety & Quality Improvement (2% of Exam)
17.1 Principles of Bioethics & Decisional Capacity 17.2 Informed Consent, Treatment Refusal & Special Scenarios 17.3 Surrogate Decision-Making, Advance Directives & Confidentiality 17.4 Patient Safety Science, Medical Error & Diagnostic Reasoning 17.5 Quality Improvement Methods, Health Disparities & Health Equity
19 Chapter 18: Perioperative Medicine & Medical Consultation
18.1 Preoperative Cardiovascular Risk Assessment 18.2 Preoperative Pulmonary Risk & Perioperative Medication Management 18.3 Perioperative Anticoagulation, Bridging & Postoperative Complications
20 Chapter 19: Ophthalmology (1% of Exam)
19.1 The Acute Red Eye & Ophthalmic Emergencies 19.2 Painless Vision Loss & Chronic Ophthalmic Disease 19.3 Uveitis, Scleritis & Orbital Disease
21 Chapter 20: Otolaryngology & Dental Medicine (1% of Exam)
20.1 Dizziness, Vertigo & Epistaxis 20.2 Ear Disorders, Hearing Loss & Upper Respiratory Infections 20.3 Oral Cavity, Salivary Gland, Laryngeal & Taste and Smell Disorders
11.6 Pharmacotherapy for Alcohol & Opioid Use Disorder
Key Takeaways Explain This Topic AI
Naltrexone is first-line for alcohol use disorder but is avoided in acute hepatitis, hepatic failure and concurrent opioid use.
Acamprosate is renally cleared and is the preferred agent when significant liver disease precludes naltrexone.
Buprenorphine must be started only after objective withdrawal has begun, or it will precipitate withdrawal.
Methadone and buprenorphine both reduce mortality in opioid use disorder, and maintenance is superior to detoxification alone.
Naloxone should be co-prescribed to patients at risk of overdose and to their household contacts.
Last updated: August 2026
1. Maintenance Pharmacotherapy for Alcohol Use Disorder
Once acute withdrawal is safely managed, pharmacotherapy should be offered to all motivated patients with moderate-to-severe AUD to prevent relapse and sustain abstinence.
Evidence-Based Maintenance Pharmacotherapies
Pharmacologic Agent Mechanism of Action & Dosing Primary Clinical Indication Organ Clearance & Hepatic / Renal Safety Rules Key Contraindications & Adverse Effects
Naltrexone (First-Line) Pure Mu-Opioid Receptor Antagonist ; blocks endogenous opioid reward pathways and blunts dopamine release in nucleus accumbens.; Dosing: 50 mg PO daily or Vivitrol 380 mg IM monthly Reduces heavy drinking days, decreases alcohol craving, and prevents binge relapse ; highly effective in patients actively trying to reduce consumption Hepatically metabolized. Safe in mild-to-moderate liver disease, but carries black box warning for dose-dependent hepatotoxicity at high doses ABSOLUTE CONTRAINDICATIONS: ; 1. Concurrent opioid use or anticipation of acute opioid analgesia (triggers severe precipitated opioid withdrawal); 2. Acute hepatitis or acute decompensated liver failure (jaundice, encephalopathy); 3. Positive urine opioid screen (requires 7-14 day opioid-free washout)
Acamprosate (First-Line) Modulates NMDA glutamate neurotransmission and enhances GABA; restores neurochemical balance disrupted by chronic alcohol dependence.; Dosing: 666 mg PO TID (two 333 mg tablets TID) Maintains complete alcohol abstinence in patients who have already achieved detoxification 100% Renally Excreted Unchanged. ; DRUG OF CHOICE IN ADVANCED LIVER DISEASE / CIRRHOSIS (zero hepatic metabolism) ABSOLUTE CONTRAINDICATION: ; Severe Renal Impairment (eGFR < 30 mL/min) ;; Dose Adjustment: Reduce dose by 50% (333 mg TID) if eGFR is 30-50 mL/min.; Adverse effects: Diarrhea, abdominal cramps
Disulfiram (Second-Line) Irreversible Aldehyde Dehydrogenase (ALDH) Inhibitor ; causes immediate toxic accumulation of Acetaldehyde within 10-20 min of ethanol ingestion.; Dosing: 250 to 500 mg PO daily Maintenance of abstinence in highly motivated, compliant patients with supervised administration (partner/clinic) Hepatically metabolized Reaction with Alcohol: Violent flushing, throbbing headache, intractable nausea/vomiting, diaphoresis, chest pain, hypotension, tachycardia, dyspnea, syncope.; Contraindications: Severe coronary artery disease, heart failure, psychosis, pregnancy; severe hepatotoxicity risk
Topiramate (Off-Label) Facilitates GABA-A neurotransmission and antagonizes AMPA/kainate glutamate receptors.; Dosing: Titrated from 25 mg to 150-300 mg/day in divided doses Reduces craving, heavy drinking days, and promotes abstinence 70% renally excreted Sedation, cognitive slowing ("Dopamax"), paresthesias, weight loss, nephrolithiasis, metabolic acidosis, angle-closure glaucoma
Gabapentin (Off-Label) Modulates voltage-gated calcium channels; increases brain GABA levels.; Dosing: 300 to 600 mg PO TID (900-1800 mg/day) Promotes abstinence, treats comorbid insomnia and mild anxiety during early sobriety 100% renally excreted; safe in liver disease Sedation, dizziness, peripheral edema; potential for misuse with opioids; adjust dose for renal impairment
- 2. Opioid Use Disorder (OUD): MAT & Acute Overdose Management
- Harm Reduction & Public Health Interventions
Comprehensive care for OUD incorporates harm reduction strategies proven to reduce mortality and transmission of bloodborne pathogens:
Naloxone Co-Prescription & Distribution: Provide take-home intranasal naloxone (4 mg) to all patients with OUD, high-dose prescription opioids (>=50 MME/day), or history of overdose.
Fentanyl Test Strip Distribution: Enables detection of synthetic fentanyl adulterants in illicit drug supplies.
Syringe Service Programs (SSPs): Sterile needle access reduces hepatitis C virus (HCV) and HIV transmission by >50%.
Infectious Screening: Routine screening for HIV, HCV (antibody + RNA reflex), Hepatitis B (HBsAg, anti-HBs, anti-HBc), and surveillance for infective endocarditis (Staphylococcus aureus).
Medication-Assisted Treatment (MAT / MOUD) Modalities
MAT Modality Pharmacology & Receptor Profile Regulatory & Dispensing Rules Clinical Pearls & Initiation Protocol Key Safety Warnings & ECG Rules
Buprenorphine (+/- Naloxone) Partial Mu-Opioid Agonist + Kappa-Opioid Antagonist ; extremely high receptor binding affinity (displaces full agonists) with a ceiling effect on respiratory depression (safer in overdose) Can be prescribed in outpatient office-based primary care settings without special SAMHSA waiver (eliminated in 2023) CRITICAL INITIATION RULE: Patient must be in objective mild-to-moderate opioid withdrawal (COWS score >=8 to 12) prior to initial dose.; Why? Administering buprenorphine while full agonists (fentanyl, heroin, oxycodone) occupy receptors causes sudden displacement, triggering severe precipitated opioid withdrawal Sublingual formulation combined with Naloxone ( Suboxone 4:1 ratio); naloxone has zero sublingual bioavailability but blocks euphoria if tablet is crushed and injected IV.; Long-acting monthly subcutaneous depot ( Sublocade ) available
Methadone Long-acting synthetic Full Mu-Opioid Agonist ; eliminates cravings and withdrawal without inducing euphoria; induces cross-tolerance Can ONLY be dispensed for OUD through federally certified Opioid Treatment Programs (OTPs) / daily methadone clinics Excellent retention in treatment; highly effective for heavy fentanyl/heroin dependence.; DRUG OF CHOICE IN RENAL FAILURE / ESRD (eliminated via fecal/hepatic routes, zero renal clearance) MANDATORY ECG MONITORING: Dose-dependent QTc Prolongation and Torsades de Pointes (especially at doses >100 mg/day or when combined with CYP3A4 inhibitors / other QT-prolonging drugs).; High risk of fatal accumulation in overdose
Extended-Release Naltrexone Full Mu-Opioid Antagonist (Vivitrol 380 mg IM monthly) Prescribed in standard outpatient medical clinics MANDATORY 7 TO 14-DAY OPIOID-FREE WASHOUT: Must verify negative urine drug screen and negative naloxone challenge before injection to avoid severe precipitated withdrawal Decreases opioid tolerance; patients who relapse after stopping naltrexone are at extreme risk of fatal overdose from standard opioid doses due to loss of tolerance
Acute Opioid Overdose & Naloxone Reversal Protocol
Clinical Triad of Acute Opioid Overdose:
Severe Respiratory Depression: Respiratory rate < 8 to 10 breaths/min , shallow chest excursions, or complete apnea with cyanosis.
Pinpoint Pupils (Miosis): Symmetric pupillary constriction (note: pupils may become dilated late due to severe hypoxic brain injury or co-ingestions like tramadol, meperidine, or sympathomimetics).
Depressed Mental Status: Stupor, unresponsiveness, or profound coma with hyporeflexia.
Emergency Resuscitation Protocol:
Airway & Ventilation First: Immediately establish patent airway, perform bag-valve-mask (BVM) ventilation with 100% Oxygen .
Naloxone Administration:
Intravenous / Intramuscular / Subcutaneous: 0.04 mg to 0.4 mg IV initial dose in suspected chronic opioid dependence; titrate incrementally every 2 to 3 minutes.
Intranasal: 4 mg (single spray in one nostril); repeat in 2-3 minutes in opposite nostril if no response.
Therapeutic Goal: Restore adequate spontaneous ventilation (RR >10-12 breaths/min) and airway reflexes , NOT complete full arousal. Rapid over-reversal precipitates acute opioid withdrawal storm (severe agitation, vomiting with aspiration risk, severe hypertension) and acute non-cardiogenic pulmonary edema .
Observation & Continuous Infusion: Naloxone has a short half-life ( 30 to 90 minutes ). Synthetic opioids (fentanyl, methadone, extended-release oxycodone) have prolonged half-lives (hours to days). Patients must be monitored for at least 4 to 6 hours for recurrent respiratory depression. If recurrent toxicity occurs, initiate a continuous IV Naloxone infusion at two-thirds of the effective waking dose per hour .