​​​​Causes​

Delirium has many​​ causes, including:

• medicine, such as certain prescription and non-prescription medicines and certain medicines taken together
  
• dehydration (not drinking enough fluids)
  
• constipation (hard poop that is difficult to pass) or diarrhea (watery poop)
  
• infection, fever, pain, or an illness that’s getting worse
• a recent fall
• poor nutrition
  
• a recent surgery or procedure
• stress
  
• problems with blood glucose (sugar) being too high or too low in someone with diabetes
• a move or recent change to where a person lives
  
• withdrawing from alcohol
• blood levels (for example, potassium, vitamin B12) that aren’t in the normal range

Risks

Delirium has many risk factors. A person may be more likely to have delirium if they:

• are older
  
• had a brain injury or have dementia
• had delirium before
  
• have depression
  
• are sick or have certain health conditions
  
• ​​​​​​​​​​​​​​have a lot of stress
  
• take many types of medicine or have recently had a change in medicines
  
• have trouble hearing or seeing
• have problems moving or getting around on their own
• are living with frailty