Delusion and delirium are cognitive disorders that can profoundly affect an individual’s perception and behaviour. Despite their overlapping symptoms, they differ significantly in their nature, causes, and treatment. In clinical practice, recognizing the differences between delusion and delirium is essential for developing appropriate treatment plans.

Dr Danish Ahmed, Senior Consultant, Mental Health And Behavioural Sciences, Max Super Speciality Hospital, Saket explains, "Delusion refers to a fixed, false belief that is held with strong conviction despite evidence to the contrary. It is a symptom commonly associated with psychotic disorders such as schizophrenia, where individuals may believe things that are implausible or impossible, such as being persecuted, having extraordinary abilities, or having a special relationship with someone famous. Delusions are typically stable over time and are not influenced by reasoning or logical arguments."

For individuals with delusions, psychiatric interventions such as antipsychotic medications and cognitive-behavioral therapy can be effective. These treatments aim to reduce the intensity of the delusions and help the individual develop more accurate perceptions of reality.

Dr Danish further elucidates, "On the other hand, delirium is a state of acute confusion and rapid changes in cognition that often result from a medical condition, substance intoxication or withdrawal, or a combination of factors. It is characterized by disturbances in attention, awareness, and cognition, and it tends to fluctuate throughout the day. Individuals experiencing delirium may have difficulty maintaining focus, exhibit disorganized thinking, or show altered levels of consciousness. Delirium is often reversible once the underlying cause is treated, such as infections, medication side effects, metabolic disturbances, or neurological conditions.''

The key distinction lies in the stability and nature of the cognitive disturbance: delusion involves a fixed false belief despite the evidence, commonly seen in psychiatric conditions, while delirium involves acute confusion and cognitive fluctuations, typically stemming from medical or environmental factors and reversible with appropriate intervention. Understanding these differences is crucial for accurate diagnosis and effective management of these conditions.

For delirium, addressing the underlying medical condition is the primary focus. This might involve treating an infection, correcting metabolic imbalances, or managing medication side effects. Supportive care, such as ensuring a calm environment and providing orientation cues, can also help reduce the symptoms of delirium.