Confusion
Confusion is a change in thinking, awareness, memory, or attention. Sudden confusion may signal a serious medical problem.
About confusion
Confusion is a change in thinking, awareness, memory, or attention. Sudden confusion may signal a serious medical problem.
What can cause it?
Sudden confusion may be caused by stroke, infection, low oxygen, low blood sugar, medicines, intoxication, dehydration, seizure, head injury, or organ failure.
It is a symptom, not a diagnosis.
What a patient may notice
Symptoms vary from person to person. Possible signs may include:
- Not knowing the time, place, or situation
- Difficulty speaking, following directions, or focusing
- New agitation, sleepiness, hallucinations, or unusual behavior
How clinicians find the cause
Emergency evaluation includes vital signs, blood sugar, neurologic examination, medication and exposure review, blood and urine tests, ECG, and imaging when indicated.
Treatment and next steps
- 1
Treatment corrects the underlying cause and protects the patient from injury.
- 2
Stroke, sepsis, overdose, low glucose, and oxygen problems require time-sensitive care.
- 3
Do not leave a suddenly confused person alone.
Supporting recovery
- Call 911 for sudden or unexplained confusion and note the last time the person was normal.
- Bring medicine containers and report possible substances, falls, fever, and diabetes.
What to expect
The outlook depends on the cause and how quickly it is treated. Confusion from low blood sugar, dehydration, a medicine effect, or infection may improve when the problem is corrected, while stroke, brain injury, low oxygen, or organ failure can cause lasting effects. Sudden confusion always requires urgent evaluation.
Possible complications
- Falls, wandering, aspiration, medication errors, or other injuries while judgment is impaired
- Delayed treatment of stroke, sepsis, low oxygen, low glucose, overdose, or another emergency
- Persistent cognitive or functional problems when the underlying cause damages the brain or other organs
When to Contact a Medical Professional
This condition can be life-threatening. Call 911 or go to the nearest emergency department. Do not delay care to visit urgent care.
Call 911 for sudden or unexplained confusion, especially with weakness, trouble speaking, fever, severe headache, injury, seizure, or difficulty waking.Get emergency help for severe trouble breathing, new chest pressure, fainting, seizure, sudden weakness on one side, uncontrolled bleeding, blue or gray lips, or a person who is difficult to wake.
Ways to lower risk
- Use medicines carefully, maintain hydration, manage chronic disease, and prevent falls.
- Older adults benefit from regular medication review.
Trusted health information
This CHS patient-education page uses original wording and links to MedlinePlus for additional information.