Symptom Finder - Hallucinations
HALLUCINATIONS
A hallucination is seeing, hearing, touching, smelling, or tasting something that is not there. Auditory hallucinations without evidence of mental deterioration usually indicate schizophrenia, but epilepsy, drug toxicity, and brain tumors must be excluded. Visual hallucinations are often the sign of drug or alcohol intoxication, but occasionally they occur in schizophrenia. Hallucinations with mental deterioration should prompt the recall of the differential diagnosis for memory loss. When faced with a hallucinating patient, think of the mnemonic MINT, and a list of possibilities can be recalled easily.
M—Mental disease brings to mind schizophrenia, manic depressive psychosis, and paranoid states.
I—Intoxication and inflammation suggest alcoholism, cannabis, lysergic acid diethylamide, bromism, various other drugs, and encephalitis, cerebral abscess (temporal lobe especially), and syphilis. The I should also suggest idiopathic disorders such as epilepsy, presenile dementia, and arteriosclerosis.
N—Neoplasm suggests brain tumors. A tumor of the occipital lobe may present with visual hallucinations, whereas a tumor of the temporal lobe causes auditory hallucinations or uncinate fits (i.e., bad smells). A tumor of the parietal lobe may present with tingling or other paresthesias of the body.
T—Trauma should suggest concussions, epidural or subdural hematomas, and depressed skull fractures.
Approach to the Diagnosis
In the workup of hallucinations, it is essential to get a drug history from a relative or friend if not from the patient. Ask about a family history of epilepsy or head trauma. A drug screen should be ordered. If there is no mental deterioration, referral to a psychiatrist may be done but an electroencephalogram (EEG) may still be indicated. A therapeutic trial of 100 mg of thiamine IV should be done if Wernicke encephalopathy or Korsakoff syndrome is suspected. With mental deterioration, a neurologist should be consulted. When there is doubt about mental deterioration, psychologic testing may be done. Computed tomography (CT) or MRI scans, EEGs, skull x-ray films, and arteriograms may be necessary in selected cases.
A hallucination is seeing, hearing, touching, smelling, or tasting something that is not there. Auditory hallucinations without evidence of mental deterioration usually indicate schizophrenia, but epilepsy, drug toxicity, and brain tumors must be excluded. Visual hallucinations are often the sign of drug or alcohol intoxication, but occasionally they occur in schizophrenia. Hallucinations with mental deterioration should prompt the recall of the differential diagnosis for memory loss. When faced with a hallucinating patient, think of the mnemonic MINT, and a list of possibilities can be recalled easily.
M—Mental disease brings to mind schizophrenia, manic depressive psychosis, and paranoid states.
I—Intoxication and inflammation suggest alcoholism, cannabis, lysergic acid diethylamide, bromism, various other drugs, and encephalitis, cerebral abscess (temporal lobe especially), and syphilis. The I should also suggest idiopathic disorders such as epilepsy, presenile dementia, and arteriosclerosis.
N—Neoplasm suggests brain tumors. A tumor of the occipital lobe may present with visual hallucinations, whereas a tumor of the temporal lobe causes auditory hallucinations or uncinate fits (i.e., bad smells). A tumor of the parietal lobe may present with tingling or other paresthesias of the body.
T—Trauma should suggest concussions, epidural or subdural hematomas, and depressed skull fractures.
Approach to the Diagnosis
In the workup of hallucinations, it is essential to get a drug history from a relative or friend if not from the patient. Ask about a family history of epilepsy or head trauma. A drug screen should be ordered. If there is no mental deterioration, referral to a psychiatrist may be done but an electroencephalogram (EEG) may still be indicated. A therapeutic trial of 100 mg of thiamine IV should be done if Wernicke encephalopathy or Korsakoff syndrome is suspected. With mental deterioration, a neurologist should be consulted. When there is doubt about mental deterioration, psychologic testing may be done. Computed tomography (CT) or MRI scans, EEGs, skull x-ray films, and arteriograms may be necessary in selected cases.