Merck Manual

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Stupor and Coma


The Manual's Editorial Staff

Last full review/revision Apr 2019| Content last modified Apr 2019
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Medical problems that affect your brain often keep you from being wide awake and thinking clearly. You may be affected only a little or a whole lot, ranging from being:

  • Slightly less alert than normal

  • Confused and not making much sense

  • Sleepy and hard to arouse

  • Unconscious

What is stupor?

Stupor is when you appear asleep or very sleepy, like you've passed out. You wake up a little if people yell at you or shake or pinch you. But after they stop doing that, you fall back asleep.

It's not considered stupor if you're just tired and sleepy from having been awake too long.

What is a coma?

Coma is when you're unconscious and can't be woken up, no matter what people try.

What causes stupor or coma?

Causes of stupor and coma are very similar, and include:     

Bodywide problems such as

Brain problems, such as

What are the symptoms of stupor or coma?

With stupor, the main symptoms are:

  • Looking asleep and being very difficult to awaken

  • When awake, not answering questions or not making sense

  • Falling back asleep when not being stimulated

With coma, people are unconscious and:

  • Don't wake up with any stimulation

  • Sometimes have unusual breathing (such as irregular or too fast or slow)

  • Sometimes have abnormalities of their eyes, such as bigger or smaller pupils, eyes that aren't moving, or eyes that are moving in strange ways

How can doctors tell if a person is in a stupor or coma?

Doctors can tell someone is in a stupor or coma by examining the person.

To find the cause of stupor or coma, doctors do tests, such as:

  • Blood tests

  • Urine tests

  • CT scan or MRI of the head 

  • EEG (a painless test that records the brain’s electrical activity)

How do doctors treat stupor and coma?

People need to be in the hospital, usually in intensive care. They often need:

  • A heart and blood pressure monitor

  • Oxygen or a breathing tube

  • IV fluids and medicine

Doctors will treat what caused the stupor or coma. Treatments may include:

  • Antidotes for drugs or poisons

  • Antibiotics for an infection

  • Brain surgery for blood or fluid build-up around the brain

Patients who remain in a coma require supportive care, such as:

  • A feeding tube for water and food

  • Frequently turning the person's body to prevent pressure sores and blood clots

  • Frequently moving the person's arms and legs to prevent stiffening of muscles (contractures)

  • A tube (catheter) in the bladder to drain urine

  • Eye drops to keep the person's eyes from drying out

How people do depends on what caused the coma. Some problems go away, and the person recovers completely. Other people wake up but have some brain damage and don't return to normal. People who have severe brain damage may stay in a coma. A few enter into a vegetative state.

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
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