8.2 Psychosis, Delirium & Substance Use
Key Takeaways
- Schizophrenia diagnosis requires at least two active-phase symptoms (one of which must be delusions, hallucinations, or disorganized speech) for at least 6 months.
- Delirium is an acute, fluctuating disturbance in attention and awareness precipitated by underlying medical issues, whereas dementia is characterized by gradual, progressive cognitive decline with intact consciousness in early stages.
- Alcohol withdrawal syndrome progresses from mild tremors and anxiety (6–24 hours) to alcoholic hallucinosis/seizures (12–48 hours) and potentially fatal delirium tremens (48–96 hours) featuring severe autonomic instability.
- First-line pharmacotherapy for moderate-to-severe alcohol withdrawal is symptom-triggered benzodiazepines (e.g., diazepam or chlordiazepoxide) guided by the Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar) protocol.
- The CAGE questionnaire is a rapid, 4-question screening tool for alcohol use disorder; a score of 2 or more points is highly sensitive and specific for clinically significant alcohol dependence.
Psychosis, Delirium, and Substance Use
Primary care physicians are frequently the first point of contact for patients experiencing acute psychotic episodes, cognitive decline, or complications related to substance use disorders. Recognizing the differences between primary psychiatric disorders and secondary, medically induced cognitive changes is critical to avoiding catastrophic clinical errors.
Schizophrenia and Psychotic Disorders
Schizophrenia is a chronic, debilitating psychiatric illness characterized by a range of cognitive, behavioral, and emotional dysfunctions.
DSM-5 Diagnostic Criteria
A diagnosis of schizophrenia requires the presence of two (2) or more of the following active-phase symptoms, each present for a significant portion of time during a 1-month period (or less if successfully treated). At least one of these symptoms must be (1), (2), or (3):
- Delusions (fixed, false beliefs not amenable to change in light of conflicting evidence).
- Hallucinations (perception-like experiences that occur without an external stimulus; auditory are most common).
- Disorganized speech (e.g., frequent derailment, loose associations, incoherence, or "word salad").
- Grossly disorganized or catatonic behavior.
- Negative symptoms (i.e., diminished emotional expression or avolition).
Duration: Continuous signs of the disturbance must persist for at least 6 months. This 6-month period must include at least 1 month of active-phase symptoms, and may include periods of prodromal or residual symptoms. If symptoms last less than 1 month, the diagnosis is Brief Psychotic Disorder; if between 1 and 6 months, it is Schizophreniform Disorder.
Positive vs. Negative Symptoms
It is clinically useful to separate schizophrenia symptoms into positive and negative domains, as they respond differently to antipsychotic pharmacotherapy:
- Positive Symptoms (Exaggeration of Normal Function): Delusions (e.g., persecutory, grandiose, referential), hallucinations, disorganized thoughts/speech, and bizarre behavior. These are primarily mediated by dopamine excess in the mesolimbic pathway and respond well to dopamine-receptor antagonists (antipsychotics).
- Negative Symptoms (Loss of Normal Function):
- Affective flattening: Reduced range and intensity of emotional expression.
- Avolition: Lack of initiation or goal-directed behavior.
- Alogia: Poverty of speech.
- Anhedonia: Inability to experience pleasure.
- Asociality: Lack of interest in social interactions. Negative symptoms are associated with structural brain changes and are highly resistant to typical (first-generation) antipsychotics, showing only modest responses to atypical (second-generation) agents.
Delirium vs. Dementia
Distinguishing acute delirium from progressive dementia is one of the most critical clinical tasks in geriatric and hospital medicine. Misdiagnosing delirium as dementia can lead to untreated life-threatening medical conditions.
| Clinical Feature | Delirium | Dementia (Major Neurocognitive Disorder) |
|---|---|---|
| Onset | Acute (hours to days) | Insidious/Gradual (months to years) |
| Course | Fluctuating (worse at night / "sundowning") | Progressive/Stable (slow decline) |
| Consciousness | Altered/Impaired (clouded, reduced awareness) | Intact/Alert (until late stages) |
| Attention | Severely disrupted (inattentive, easily distracted) | Relatively preserved (initially) |
| Hallucinations | Common (often visual or tactile, vivid) | Uncommon (except in specific types like Lewy Body) |
| Reversibility | Potentially reversible (resolves with treatment of cause) | Irreversible/Progressive |
| Underlying Cause | Acute medical illness, drug toxicity, electrolyte imbalance | Primary neurodegenerative disease (e.g., Alzheimer's) |
Clinical Diagnosis of Delirium
The Confusion Assessment Method (CAM) is widely used for bedside diagnosis. Delirium is diagnosed if the patient exhibits:
- Acute onset and fluctuating course AND
- Inattention AND
- EITHER Disorganized thinking OR Altered level of consciousness.
Common medical causes of delirium include infections (e.g., urinary tract infections, pneumonia), medications (e.g., anticholinergics, benzodiazepines, opioids), electrolyte imbalances (e.g., hyponatremia, hypercalcemia), hypoxia, and withdrawal states.
Alcohol Use Disorder and Withdrawal
Alcohol withdrawal is a potentially life-threatening medical emergency that requires prompt recognition and standardized monitoring.
CAGE Questionnaire
The CAGE questionnaire is an exceptionally high-yield, 4-question screening tool used to identify alcohol abuse or dependence:
- Cut down: "Have you ever felt you should Cut down on your drinking?"
- Annoyed: "Have people Annoyed you by criticizing your drinking?"
- Guilty: "Have you ever felt bad or Guilty about your drinking?"
- Eye-opener: "Have you ever had a drink first thing in the morning to steady your nerves or get rid of a hangover (Eye-opener)?"
Scoring: Each "yes" answer equals 1 point. A total score of 2 or more is considered clinically significant and suggests alcohol misuse or dependence, requiring further clinical evaluation.
Stages of Alcohol Withdrawal
Alcohol withdrawal is characterized by a predictable progression of symptoms as blood alcohol levels decline:
- Mild Withdrawal (6 to 24 hours since last drink): Tremulousness, mild anxiety, palpitations, diaphoresis, headache, insomnia, and gastrointestinal upset. Vital signs show mild tachycardia and hypertension. Consciousness remains clear.
- Alcoholic Hallucinosis / Withdrawal Seizures (12 to 48 hours):
- Hallucinosis: Visual, tactile, or auditory hallucinations. Unlike delirium, the patient has a clear sensorium and intact orientation.
- Seizures: Generalized tonic-clonic seizures, often occurring in bursts.
- Delirium Tremens (DTs) (48 to 96 hours): The most severe manifestation, carrying a significant mortality rate (up to 5% if untreated). Characterized by:
- Marked disorientation and confusion (delirium).
- Autonomic instability: Severe tachycardia, tachypnea, malignant hypertension, hyperthermia/fever, and drenching sweats.
- Visual and tactile hallucinations (e.g., feeling bugs crawling on skin - formication).
- Severe psychomotor agitation.
Clinical Management of Alcohol Withdrawal
- Assessment Tool: The Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar) scale monitors withdrawal severity across 10 symptom categories. A score <8 indicates mild withdrawal, 8–15 moderate, and >15 severe.
- First-line Therapy: Benzodiazepines are the gold standard. They act as cross-tolerant GABA-A receptor agonists, replacing the inhibitory effects of alcohol.
- Symptom-triggered regimen: Benzodiazepines are administered only when the CIWA-Ar score exceeds a threshold (typically >= 8 or 10). This reduces total drug exposure.
- Fixed-schedule regimen: Administered at regular intervals and tapered down; used for patients with a history of withdrawal seizures or DTs.
- Agent Selection: Long-acting agents (e.g., chlordiazepoxide or diazepam) are preferred due to a smoother self-tapering effect. In patients with liver failure or advanced age, short-acting agents that do not require hepatic oxidation (mnemonic LOT: Lorazepam, Oxazepam, Temazepam) are mandatory.
- Adjuvant Therapy: Thiamine (vitamin B1) must be administered before any glucose-containing fluids to prevent the onset of Wernicke-Korsakoff syndrome (triad of encephalopathy, oculomotor dysfunction, and ataxia).
An 82-year-old female with a history of mild cognitive impairment is brought to the emergency department by her family due to a sudden onset of confusion, agitation, and visual hallucinations starting yesterday. Her family notes that she was talking to imaginary people this morning, but seemed relatively clear and alert this afternoon before becoming highly agitated again this evening. On examination, she is distracted, unable to count backward from 20, and her urinalysis is positive for leukocytes and nitrites. Which of the following features is most critical in distinguishing this patient's acute presentation from her baseline dementia?
A 45-year-old male is admitted to the medical ward for treatment of a compound lower leg fracture. Approximately 72 hours after admission, the patient becomes highly disoriented, agitated, and reports seeing "insects crawling all over the walls." On physical examination, he is diaphoretic, his temperature is 38.8°C (101.8°F), heart rate is 126 bpm, and blood pressure is 172/104 mmHg. What is the most likely diagnosis and the first-line pharmacotherapeutic class for management?
A 23-year-old male is brought to the clinic by his parents due to a change in his behavior over the past 8 months. He has isolated himself in his room, dropped out of university, and ceased all social activities. He states that the television is broadcasting secret messages specifically to him and that he hears whispering voices in his room when he is alone. On examination, his speech is disorganized, and he demonstrates a flat affect and poor hygiene. Which of the following combinations of symptoms represents the negative symptom domain of this patient's condition?