Behavior - unusual or strange

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Treatment

Behavior - unusual or strange

Definition:

Unusual or strange behavior involves actions that are not typical of that individual.

Alternative Names:

Acting strangely

Considerations:

There are many causes of unsual or strange behavior, including numerous medical and psychiatric illnesses. Two of the more common causes are delirium and dementia:

Delirium is characterized by the following:
- sudden decreased level of consciousness
- association with medical illness, particularly high fever
Dementia is characterized by the following:
- chronic, progressive loss of cognitive function
- association with brain disorders

Common Causes:

Causes in older people include the following:

Malnutrition (particularly vitamin B12 and thiamine deficiency)
Medications
Alcohol in excess
Chronic exposure to cold (hypothermia)
Emotional problems (depression or feeling useless)
Head injury (subdural hematoma)
Unfamiliar surroundings
Dehydration
Electrolyte abnormality
Infection (including pneumonia, gastroenteritis, urinary tract infection)
Thyroid disorders (either underactive or overactive)
Alzheimer's disease

Causes in people of all ages include the following:

Anxiety, emotional problems
Side effects of medication for attention deficit disorder, such as Ritalin
Side effects of antidepressants, such as Prozac
Illicit drug use (particularly stimulants such as amphetamines and cocaine)
Diseases affecting the nervous system (neurological diseases)
Non-neurological diseases, particularly with fever (for example, pneumonia)
Low or high thyroid function
Environmental hazards

Review Date: 1/25/2003
Reviewed By: David Taylor, M.D., Department of Psychiatry, University of Pennsylvania Medical Center, Philadelphia, PA. Review provided by VeriMed Healthcare Network.

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