People with progressive supranuclear palsy (PSP) develop a range of difficulties with balance, movement, vision, speech and swallowing.

The condition tends to develop gradually, which means it can be mistaken for another, more common, condition at first. 

The symptoms typically become more severe over several years, although the speed at which they worsen varies.

Most people with PSP will not have all of the symptoms.

The initial symptoms of PSP can include:

• sudden loss of balance when walking that usually results in repeated falls, often backwards
• extreme tiredness
• slow, quiet or slurred speech
• changes in personality and behaviour
• difficulties with tasks involving planning and organisation
• a dislike of bright lights (photophobia)
• difficulty controlling the eye muscles (particularly problems with looking up and down)
• blurred or double vision

Some people have early symptoms that are very similar to those of Parkinson's disease, such as muscle stiffness and slow movement.

The symptoms of PSP usually get worse over time, but how the condition progresses can vary from person to person.

Worsening balance and mobility problems may mean that walking becomes impossible and a wheelchair is needed.

Controlling the eye muscles will become more difficult, increasing the risk of falls and making everyday tasks, such as reading and eating, more problematic.

New symptoms can also develop at this stage, such as:

• problems swallowing (dysphagia)
• eyelid problems, such as twitching or drooping eyelids
• disturbed sleep
• slowness of thought and some memory problems
• muscle stiffness, particularly in the neck
• neck, back and joint pain
• headaches

As PSP progresses to an advanced stage, people with the condition normally begin to experience increasing difficulties controlling the muscles of their mouth, throat and tongue.

Speech may become increasingly slow and slurred, making it harder to understand.

There may also be some increasing problems with thinking, concentration and memory.

The loss of control of the throat muscles can lead to severe swallowing problems.

This may mean a feeding tube is required at some point. This is to prevent choking and chest infections  caused by fluid or small food particles passing into the lungs.

Many people with PSP also develop problems with their bowel and bladder function. Constipation and difficulty passing urine are common, as is the need to pass urine several times during the night.

Some people may lose control over their bladder or bowel movements (incontinence).