Delirium is an abrupt change in the brain that causes mental confusion and emotional disruption. It makes it difficult to think, remember, sleep, pay attention, and more. You might experience delirium during alcohol withdrawal, after surgery, or with dementia. Delirium is usually temporary and can often be treated effectively.

Delirium is categorized by its cause, severity, and characteristics, and can be categorized into three types:

• Delirium tremens is a severe form of the condition experienced by people who are trying to stop drinking.
• Hyperactive delirium is characterized by being highly alert and uncooperative.
• Hypoactive delirium is more common. With this type, you tend to sleep more and become inattentive and disorganized with daily tasks.

Diseases that cause inflammation and infection, such as pneumonia, can interfere with brain function. Additionally, taking certain medications (such as blood pressure medicine) or misusing drugs can disrupt chemicals in the brain. Alcohol withdrawal and eating or drinking poisonous substances can also cause delirium. If you’re over 65 or have numerous health conditions, you’re more at risk for delirium. Others who have increased risk of delirium include:

• People who’ve had surgery
• People withdrawing from alcohol and drugs
• Those who’ve experienced conditions that damage the brain (for example, stroke and dementia)
• People who are under extreme emotional stress

The following factors may also contribute to delirium:

• Sleep deprivation
• Certain medications
• Dehydration
• Poor nutrition
• Infections such as a urinary tract infection

Some of the Symptoms of delirium include:

• Not thinking or speaking clearly
• Sleeping poorly and feeling drowsy
• Reduced short-term memory
• Loss of muscle control (for example, incontinence)

Depending on the cause of the delirium, treatment may include taking or stopping certain medications. In older adults, an accurate diagnosis is important for treatment, as delirium symptoms are similar to dementia, but the treatments are very different.