Hydrocephalus, or excess fluid in the brain, causes slightly different symptoms depending on the type of hydrocephalus and the age of the person affected.

Babies born with hydrocephalus (congenital hydrocephalus) often have distinctive physical features.

These can include:

• an unusually large head
• a thin and shiny scalp with easily visible veins
• a bulging or tense fontanelle (the soft spot on top of a baby's head)
• downward looking eyes

Congenital hydrocephalus can also cause:

• poor feeding
• irritability
• vomiting
• sleepiness
• muscle stiffness and spasms in your baby's lower limbs

Congenital hydrocephalus is sometimes found before a baby is born during an ultrasound scan.

However, it's usually diagnosed soon after birth during the newborn physical examination. The condition may be suspected if your baby's head is larger than normal.

Hydrocephalus that develops in children or adults (acquired hydrocephalus) can cause headaches.

The headache may be worse when you wake up in the morning. This is because the fluid in your brain does not drain as well while you're lying down and may have built up overnight.

Sitting up for a while may improve the headache. However, as the condition progresses, headaches may become continuous.

Other symptoms of acquired hydrocephalus include:

• neck pain
• feeling sick
• being sick – this may be worse in the morning
• sleepiness – can progress to a coma
• changes in your mental state, such as confusion
• blurred vision or double vision
• difficulty walking
• an inability to control your bladder (urinary incontinence) and, in some cases, your bowel (bowel incontinence)

Call a GP or use NHS 111 if you think you or your child may have symptoms of hydrocephalus.

The symptoms of normal pressure hydrocephalus (NPH) tend to affect older people and usually develop slowly, over many months or years.

NPH has 3 sets of distinctive symptoms. It affects:

• how you walk (mobility)
• the urinary system
• mental abilities

How you walk

The first noticeable symptom of NPH is a change in how you walk (your gait). You may find it increasingly difficult to take the first step when you want to start walking.

Some people have described it as feeling as though they're frozen to the spot. You may also shuffle rather than take proper steps.

As the condition progresses, you may become increasingly unsteady on your feet and be more likely to fall, particularly when turning.

Urinary symptoms

The change in the way you walk is often followed by bouts of urinary incontinence, which may include symptoms such as:

• a frequent need to pee
• an urgent need to pee
• loss of bladder control

Mental abilities

The normal thinking process also starts to slow down. For example, a person may:

• be slow to respond to questions
• react slowly to situations
• be slow to process information

These symptoms may be a sign of mild dementia. They should start to improve when NPH is treated.

Read more about how NPH is treated.