**Question:** A 40 year old male, with history of daily alcohol consumption for the last 7 years, is brought to the hospital emergency room with acute onset of seeing snakes all around him in the room, not recognizing family members, violent behavior and tremulousness for few hours. There is history of his having missed the alcohol drink since 2 days. Examination reveals increased blood pressure, tremors, increased psychomotor activity, fearful affect, hallucinatory behaviour, disorientation, impaired judgement and insight. He is most likely to be suffering from-

A. Alcohol Withdrawal Syndrome
B. Schizophrenia
C. Acute Hallucinatory Psychosis
D. Parkinson's Disease

**Correct Answer:** A. Alcohol Withdrawal Syndrome

**Core Concept:**

Alcohol withdrawal syndrome (AWS) is a clinical condition that occurs in individuals who abruptly stop or significantly reduce alcohol consumption after prolonged use. The syndrome is characterized by a series of symptoms that develop as the body tries to adjust to the reduced alcohol levels, including central nervous system dysfunction. AWS is a manifestation of the complex interplay between central nervous system and peripheral systems, with the involvement of neurotransmitters, receptors, and physiological changes.

**Why the Correct Answer is Right:**

The correct answer is A. Alcohol Withdrawal Syndrome because:

1. The patient presents with acute onset symptoms, which are not consistent with chronic neurological disorders like Parkinson's Disease (D) or Schizophrenia (B). The abrupt onset, fluctuating symptoms, and the history of alcohol consumption are indicative of AWS.
2. The patient shows symptoms like hallucinations (hallucinatory psychosis), tremors, increased psychomotor activity, and impaired judgement and insight, which are all consistent with AWS. Hallucinations, tremors, and cognitive dysfunction are common manifestations of AWS.
3. The patient has missed alcohol for 2 days, which is a risk factor for AWS due to its rapid onset and severity.

**Why Other Options are Incorrect:**

B. Schizophrenia is a chronic mental disorder characterized by positive symptoms (hallucinations and delusions), negative symptoms (flat affect and social withdrawal), and cognitive deficits (impaired attention, memory, and decision-making). The presented symptoms are more consistent with AWS than schizophrenia.

C. Acute Hallucinatory Psychosis is a less specific term for AWS and does not account for the other clinical features like tremors, increased psychomotor activity, impaired judgement, and insight.

D. Parkinson's Disease is a degenerative neurological disorder affecting motor function, characterized by tremors, rigidity, bradykinesia, and resting tremors, not the acute onset, fluctuating symptoms, and cognitive dysfunction seen in AWS.

**Clinical Pearls:**

1. Alcohol withdrawal syndrome is a potentially life-threatening condition that can cause seizures, delirium tremens (DTs), and rarely, cerebral oedema (Wernicke-Korsakoff syndrome).
2. The recommended management includes gradual alcohol cessation under medical supervision, benz