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What is encephalitis? — Encephalitis is a rare condition that causes inflammation of the brain. It is most often caused by a virus.
What are the symptoms of encephalitis? — Symptoms include:
Confusion or trouble thinking
Trouble swallowing or speaking
Saying things that do not make sense
Clumsiness or trouble walking
Weak muscles on 1 side of the body
Seizures – Seizures are waves of abnormal electrical activity in the brain. They can make people pass out, or move or behave strangely.
Will I need tests? — Yes. Your doctor will learn about your symptoms and do an exam. He or she will do tests to see what caused your encephalitis and to check that you do not have a different condition. Tests include:
Blood tests
Imaging tests – These include an MRI or CT scan (a special kind of X-ray). These tests create pictures of the inside of the brain.
A lumbar puncture (sometimes called a "spinal tap") – During this procedure, a doctor puts a thin needle into your lower back and removes a small amount of spinal fluid. Spinal fluid is the fluid that surrounds the brain and spinal cord. He or she will do lab tests on the spinal fluid.
How is encephalitis treated? — Some types of encephalitis can be treated with medicines that fight the infection. These are given in a hospital, usually through a thin tube that goes into a vein, called an "IV." They might include:
Acyclovir (brand name: Zovirax), which is used to treat infections caused by certain viruses
Antibiotics, which are medicines used to treat infections caused by bacteria
When encephalitis is related to something other than an infection, doctors can try to treat the cause. Some types of encephalitis are not treated with medicines and must get better on their own.
Can encephalitis be prevented? — Sometimes. Some of the viruses that cause encephalitis are spread by mosquito or tick bites. You can lower your chances of getting encephalitis by avoiding these types of bites. To do this, you can:
Stay inside at dawn and dusk, when mosquitoes are more likely to be around.
Wear shoes, long-sleeved shirts, and long pants when you go outside, especially at dusk.
Wear bug spray on your skin. On your clothes and gear, use bug repellents that have a chemical called "permethrin."
Drain areas of standing water if possible, such as wading pools, buckets, and potted plants with saucers. Mosquitoes breed in standing water.
Check your body for ticks after being outdoors or around dogs.
All topics are updated as new evidence becomes available and our peer review process is complete.
This topic retrieved from UpToDate on: Mar 30, 2020.
Topic 17213 Version 8.0
Release: 28.2.2 - C28.105
© 2020 UpToDate, Inc. and/or its affiliates. All rights reserved.

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