The following symptoms and complaints may indicate hallucinations:
Pathognomonic (indicative of a disease).
- Sensory illusion without a real correlate.
Warning signs (red flags)
- Anamnestic information:
- Alcohol dependence
- Drug use
- Neurological diseases
- Psychiatric diseases
- Auditory hallucinations → think: psychotic illness (e.g., schizophrenia, psychotic depression).
- Olfactory hallucination → think of: Temporallapenepilepsy
- Tactile hallucination → think of: Alcohol withdrawal; occasionally also in cocaine abuse.