What Is Increased Intracranial Pressure (ICP)?

Medically Reviewed by Christopher Melinosky, MD on August 16, 2023
3 min read

Headaches are a common complaint. Most people have headaches at some time in their lives. But you can't fix all headaches with some over-the-counter pain medicine and a nap. 

Sometimes your headache is a sign of a serious medical emergency called increased intracranial pressure (ICP). ICP is what happens when there is excess fluid or swelling inside your skull. The increase in volume over-fills the limited space in your skull and puts pressure on your brain. 

One key symptom of increased intracranial pressure may be a bad headache. ICP is a medical emergency. You should call for help immediately if you think you are experiencing increased intracranial pressure. 

One of the most common causes of increased intracranial pressure is an injury to your brain or skull. The trauma leads to bleeding or swelling inside your skull. That pressure from the excess fluid or the swelling can harm your brain tissue or your spinal column

You should talk to your doctor if you have had a head injury. They may want to monitor you for possible increased ICP.

A stroke is another common reason for increased pressure in your skull. Some types of stroke cause blood vessels in your brain to burst. The blood pools in and around your brain. This causes pressure. Call 911 right away if you think you are having a stroke. 

Other causes of increased intracranial pressure include:

ICP may start with a headache. The headache may be sudden and excruciating. It might also stay mild and steadily get worse over time. But the building pressure on your brain will cause other symptoms. These symptoms may clue you in that your headache is not just normal discomfort.

Other symptoms of increased intracranial pressure include:

  • Blurred vision
  • Vomiting
  • Weakness
  • Difficulty moving or talking
  • Feeling less alert
  • Fatigue or sleepiness
  • Behavior changes

Contact your doctor right away if you have a headache along with any of these symptoms.

When you see a doctor for possible ICP, they may do several of the following tests to diagnose the issue.

Physical exam. Your doctor will ask you about any recent injuries or illnesses. They may check your blood pressure and examine your eyes for signs of neurological problems. They will also test your senses, balance, and mental status.

Spinal tap. Your doctor may use a needle to check the pressure of the fluid around your spine. This can indicate that there is increased pressure around your brain.

CT scan or MRI. Your doctor can see images of your brain by using CT or MRI scans. They will show any injuries and the location of swelling or fluid build-up.

Your treatment will depend on the reason for your intracranial swelling. Your doctor will choose a treatment option for you once they know what is causing the problem.

Medication. Some medications can reduce swelling in your brain. If you have a blood clot in your brain, your doctor may give you medicine to dissolve it.

Draining fluid. Your doctor can place a device called an external ventricular drain (EVD). This will allow excess fluid to flow out of your skull through tubes. Your doctor can put in a shunt if you need drainage from your brain for a longer time. A shunt is a tube placed inside your body to direct fluid from your brain into your abdomen.

Surgery. Sometimes your doctor will need to operate to relieve the pressure inside your brain. The type of surgery will depend on the cause of the pressure. Doctors may need to repair an injury, stop any bleeding, or remove a tumor.

Any treatment for ICP will be more effective the sooner you get it. Waiting to get medical attention puts you at risk for brain damage. ‌Intracranial pressure is a medical emergency. Call a doctor right away if you suspect you or someone you know has increased intracranial pressure.