Common Signs and Symptoms of a Brain Tumor

Brain tumors can cause many different signs and symptoms. What a person feels depends on where the tumor is located, how big it is, and how fast it is growing. This page explains the most common warning signs in simple words, along with some important considerations.

Headaches

Headaches are one of the most common signs of a brain tumor. About half of all people with brain tumors have headaches at some point. However, most headaches are not caused by brain tumors.

What brain tumor headaches may feel like:

Often worse when you wake up in the morning and get better during the day
May feel like a dull pressure or ache, similar to a tension headache
Can get worse when coughing, sneezing, bending over, or straining
Usually do not go away with regular pain medicine
May be different from your normal headaches or get worse over time

Important to know: A headache by itself is rarely the only sign of a brain tumor. If your headache comes with other symptoms like vision changes, weakness, or confusion, talk to your doctor right away.

Seizures

Seizures happen when there is unusual electrical activity in the brain. They are a common early sign of a brain tumor, occurring in about 30 to 60 percent of patients. For some people, a seizure is the very first sign that something is wrong.

What seizures can look like:

Shaking or jerking movements in part or all of the body
Staring blankly or appearing “spaced out”
Strange sensations like tingling, smells, or tastes that are not there
Brief moments of confusion or loss of awareness

Important to know: Seizures can happen even in people who have never had them before. If you or someone you know has a seizure for the first time, it is important to get medical help right away.

Thinking and Memory Problems

Brain tumors often affect how people think, remember, and pay attention. Research shows that about 80 to 90 percent of brain tumor patients experience some type of thinking problem. These changes can be subtle at first and may be noticed by family members before the patient realizes them.

Common changes include:

Trouble remembering new information or recent events
Difficulty concentrating or staying focused
Problems finding the right words or following conversations
Slower thinking or trouble making decisions
Confusion about everyday things

Important to know: Family members often notice these changes before patients do. Sometimes thinking problems show up on tests before changes appear on brain scans.

Weakness or Numbness

Tumors can press on parts of the brain that control movement and feeling. About one-third of patients have weakness or numbness when first diagnosed.

What this may feel like:

Weakness in one arm, one leg, or one side of the body
Trouble gripping things or picking up objects
Numbness or tingling, often on one side
Feeling clumsy or dropping things more often

Important to know: The weakness or numbness usually affects only one side of the body. This happens because of how the brain is organized, with each side controlling the opposite side of the body.

Balance and Coordination Problems

Tumors in certain parts of the brain can make it hard to keep your balance or coordinate your movements. Nearly half of brain tumor survivors have balance problems.

Signs to watch for:

Feeling unsteady when walking
Trouble with balance, especially when standing or moving
Dizziness or feeling like the room is spinning
Difficulty with tasks that need careful hand movements

Important to know: Balance problems are especially common when tumors grow near the cerebellum, the part of the brain at the back of the head that controls coordination.

Vision and Hearing Changes

Depending on where a tumor is located, it can affect your eyes or ears. About 16 percent of patients have reduced vision, and nearly 15 percent experience double vision before diagnosis.

Vision changes may include:

Blurry or double vision
Loss of side vision (seeing only what is straight ahead)
Flickering eyes or trouble controlling eye movements
Partial or complete loss of sight in one or both eyes

Hearing changes may include:

Ringing in the ears (called tinnitus)
Hearing loss in one ear
Dizziness along with hearing problems

Important to know: Vision changes can develop slowly, so regular eye exams are important. Opticians and eye doctors can sometimes spot signs of increased brain pressure during a routine checkup.

Speech and Language Difficulties

Brain tumors can make it hard to speak, understand words, or communicate. At least one in five brain tumor patients has speech and language problems.

What this may look like:

Trouble finding the right words
Slurred or unclear speech
Difficulty understanding what others say
Problems reading or writing

Important to know: Word-finding problems are often one of the first language symptoms, even before other signs appear. These difficulties may be subtle at first and gradually get worse.

Nausea and Vomiting

Feeling sick to your stomach and throwing up can be signs of a brain tumor, especially when combined with headaches. These symptoms happen because of increased pressure inside the skull.

What to notice:

Feeling sick in the morning that gets better as the day goes on
Nausea that gets worse when you change position quickly
Vomiting with no clear cause like stomach flu or food poisoning
Symptoms that last more than a week

Important to know: Nausea and vomiting from a brain tumor are rarely the only symptoms. They usually happen along with headaches or other warning signs.

Personality and Behavior Changes

Brain tumors can change how a person acts, feels, and relates to others. These changes can be hard to recognize because they develop slowly.

Changes may include:

Mood swings or feeling more emotional than usual
Acting differently than before, like being more irritable or withdrawn
Loss of interest in activities once enjoyed
Depression, anxiety, or unusual fears
Acting in ways that seem out of character

Important to know: These changes are most common when tumors are in the frontal lobe, the part of the brain behind your forehead. Family members and friends often notice personality changes before the patient does.

Fatigue and Drowsiness

Extreme tiredness is one of the most common symptoms reported by brain tumor patients. Studies show that fatigue affects between 25 and 90 percent of people with brain tumors.

What this may feel like:

Feeling exhausted even after rest or sleep
Having much less energy than usual
Needing to sleep more than normal
Feeling too tired to do everyday activities

Important to know: Fatigue from brain tumors is different from normal tiredness. It does not get better with rest and can make other symptoms feel worse. This kind of tiredness can affect work, relationships, and quality of life.

Mass Effect: When a Tumor Takes Up Space

“Mass effect” is a medical term that describes what happens when a brain tumor grows and takes up space inside the skull. Because the skull is a hard, closed space, there is no room for anything extra. When a tumor grows, it pushes against the healthy brain around it.

Why this matters:
The brain sits inside the skull along with blood and a clear fluid called cerebrospinal fluid (CSF). Together, these fill the skull completely. When a tumor starts to grow, it pushes on the brain tissue and blood vessels around it. The brain tries to make room by moving fluid around, but it can only do this for so long.

What happens next:
As the tumor gets bigger, the pressure inside the skull goes up. Doctors call this “increased intracranial pressure” or “ICP” for short. This increased pressure is responsible for many brain tumor symptoms. The pressure can build slowly over days to weeks, and the body may adjust at first. But when the brain can no longer make room, the pressure rises quickly and causes more noticeable symptoms.

Signs of increased pressure include:

Headaches that are often worse in the morning or after physical activity
Feeling sick to your stomach or throwing up
Feeling very tired or sleepy
Dizziness or trouble with balance
Changes in thinking, memory, or behavior
Weakness in arms or legs
Numbness or tingling
Vision problems
Trouble speaking
Feeling confused or less alert

Swelling can make it worse:
Brain tumors can also cause swelling in the brain, called edema. This happens when blood vessels near the tumor start to leak fluid into the brain tissue. This extra fluid takes up even more space and adds to the pressure inside the skull.

Important to know: Increased pressure in the brain is a serious condition that needs medical attention right away. If you notice headaches getting worse, especially with other symptoms like confusion, weakness, or vision changes, contact your healthcare team promptly. Doctors have ways to measure and treat increased brain pressure, including medicines to reduce swelling and procedures to relieve pressure.

When to See a Doctor

Most of these symptoms can also be caused by other health problems that are not brain tumors. However, you should talk to a doctor if you have:

A new or different kind of headache that does not go away
A seizure for the first time
Several symptoms happening together
Symptoms that are getting worse over time
Any sudden changes in vision, speech, or movement

Your doctor can do tests to find out what is causing your symptoms. The earlier a brain tumor is found, the more treatment options may be available.

A Note for Loved Ones

Family members and caregivers often notice brain tumor symptoms before patients do. This is especially true for subtle changes in thinking, memory, or personality. If you notice changes in someone you care about, gently encourage them to see a doctor. Your observations can be very helpful to the medical team.

Disclaimer: This information is for general education only and is not medical advice. It should not be used to diagnose, treat, or rule out any condition. If you notice new, changing, or concerning symptoms, contact your healthcare provider. Do not delay seeking medical care because of something you read here. Brain Tumor Network is not responsible for any actions taken based on this information.

Return to all Blogs