Nursing care
Substance Use Disorder nursing care: what to assess and what to do first
Written and reviewed by Dana Whitfield, RN, MSN · 5 min read · Updated September 2026
Short answer
Substance use disorder nursing care starts with a non-judgemental history, a validated withdrawal assessment tool, and vital sign monitoring, because the substance involved determines the danger. Alcohol and benzodiazepine withdrawal can be fatal through seizures or delirium tremens; opioid withdrawal is intensely uncomfortable but rarely lethal on its own. Treat pain and dignity as clinical priorities, not afterthoughts.
Recognising it at the bedside
Substance use disorder rarely announces itself on admission. It shows up as a patient who is unexpectedly anxious two hours post-op, a trauma admission whose blood alcohol level does not match their story, or someone requesting doses of PRN opioids well above what their injury would predict. Track marks, poor dentition, hepatomegaly, and a heart rate that will not settle are all cues, but the most reliable signal is often the history itself: ask directly about frequency, quantity, and last use, and ask it the same way you ask about allergies.
Screening tools matter more than instinct here. CIWA-Ar for alcohol and COWS for opioids give you a reproducible number you can trend across a shift and hand off to the next nurse. A one-off gut feeling that "something is off" does not travel between shifts; a CIWA-Ar score of 12 does. Use the tool at admission for anyone with a positive screen, not only for patients who tell you they drink or use.
Why the classic presentation misleads
Patients and even some clinicians assume opioid withdrawal is the dangerous one because it looks dramatic: vomiting, diarrhoea, piloerection, and agitation that can fill a room. Alcohol withdrawal, in contrast, can start quietly with tremor and mild anxiety, which lulls staff into thinking it is the lesser problem. Alcohol withdrawal can kill and opioid withdrawal is miserable but rarely fatal, which is the opposite of what patients expect, and it is the single most important reframe for anyone caring for this population.
The mechanism explains the mismatch. Chronic alcohol use downregulates GABA receptors and upregulates NMDA receptors; sudden cessation leaves the brain in a state primed for seizures and autonomic storm, which is what makes delirium tremens lethal without treatment. Opioids act on a different system entirely and their withdrawal, while brutal, does not carry the same seizure or cardiovascular collapse risk. Nurses who triage by symptom severity alone will systematically underrate the quiet alcohol case and overrate the loud opioid one.
Priority nursing actions
Airway, breathing, circulation still comes first, but for this population it is followed immediately by a withdrawal risk stratification. Any patient with a known or suspected alcohol use history needs vital signs and a CIWA-Ar score on a fixed schedule, not just when they look unwell, because deterioration in alcohol withdrawal can move from tremor to seizure in hours. Seizure precautions go up alongside the first assessment, not after the first symptom.
Beyond monitoring, treat the whole person. Manage pain honestly rather than assuming drug-seeking behaviour, because untreated pain in a person with substance use disorder drives both poor outcomes and mistrust of the care team. Involve the patient in decisions about their treatment plan where possible, and loop in social work or an addiction medicine consult early rather than at discharge. A calm, private environment reduces the autonomic load that worsens both alcohol and opioid withdrawal.
Labs and diagnostics to expect
A basic metabolic panel and magnesium and phosphate levels are standard, since chronic alcohol use depletes both and low magnesium lowers the seizure threshold further. Liver function tests and a coagulation panel flag hepatic damage that changes how you dose sedating medications. A blood alcohol level on admission, where available, helps calibrate how much time you have before withdrawal symptoms are expected to begin.
For suspected opioid use, a urine toxicology screen confirms the substance class but will not tell you dose or duration, so treat it as one data point rather than the whole picture. An ECG is worth obtaining early if there is any cardiac history or electrolyte derangement, since QT prolongation changes which medications are safe to give. None of these results should delay starting a symptom-triggered protocol if the patient is clinically withdrawing.
Complications and their early signs
Delirium tremens is the complication to fear with alcohol withdrawal: watch for escalating confusion, hallucinations, marked autonomic instability with tachycardia and hypertension, and fever. It typically follows a seizure or emerges after 48 hours if withdrawal goes untreated, and it carries a real mortality risk without aggressive benzodiazepine management. A patient who was oriented on your last round and is now picking at the air deserves an immediate reassessment, not a wait-and-see approach.
Opioid withdrawal complications are different in kind. Watch for dehydration and electrolyte imbalance from prolonged vomiting and diarrhoea, and for aspiration risk in a patient who is vomiting while drowsy from other medications. Neither alcohol nor opioid withdrawal should be managed with restraints as a first response to agitation; restraints increase autonomic arousal and delay the pharmacological treatment that actually resolves the underlying problem.
Teaching that changes outcomes
Discharge teaching for substance use disorder works best when it is specific and free of moral framing. Explain what withdrawal will feel like if it recurs outside hospital, when to seek emergency care, and that stopping alcohol abruptly after this admission without medical support is dangerous rather than admirable. Patients who understand the seizure risk of unsupervised alcohol withdrawal are more likely to seek a supervised taper next time.
Naloxone education belongs in every discharge involving opioid use, for the patient and for whoever they live with, along with a concrete referral rather than a pamphlet: a named clinic, a phone number, an appointment time if one can be arranged before discharge. Framing relapse as a feature of a chronic relapsing condition rather than a moral failure keeps patients engaged with care instead of avoiding it out of shame.
The next step on this is the same as on everything else here: answer questions and read the rationales. Our mental health practice questions are the closest set to what this page covers.
Common questions
Which substance use disorder withdrawal is most dangerous to a patient?
Alcohol and benzodiazepine withdrawal carry the highest mortality risk, primarily through seizures and delirium tremens. Opioid withdrawal causes severe discomfort but is rarely life-threatening on its own unless complicated by dehydration or aspiration.
What assessment tool do nurses use for alcohol withdrawal?
CIWA-Ar (Clinical Institute Withdrawal Assessment for Alcohol, revised) is the standard tool, scoring symptoms like tremor, sweating, agitation, and hallucinations to guide symptom-triggered medication dosing.
How does an NCLEX question distinguish substance use disorder from drug-seeking behaviour?
Look for the framing: questions testing substance use disorder as a diagnosis expect you to recognise it as a chronic medical condition requiring assessment and treatment, not to label the patient's requests as manipulative. Answers that jump to accusing the patient are almost always wrong.
Should a nurse give PRN opioids to a patient with a known opioid use disorder?
Yes, if there is a legitimate indication such as post-operative pain, treat it as you would in any other patient. Undertreating pain out of suspicion increases distress and does not reduce misuse risk; it damages trust and can worsen outcomes.
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