The symptoms of Alzheimer's disease progress slowly over several years. Sometimes these symptoms are confused with other conditions and may initially be put down to old age.
The rate at which the symptoms progress is different for each individual.
In some cases, other conditions can be responsible for symptoms getting worse.
These conditions include:
As well as these conditions, other things, such as certain medicines, can also worsen the symptoms of dementia.
Anyone with Alzheimer's disease whose symptoms are rapidly getting worse should be seen by a doctor so these can be managed.
There may be reasons behind the worsening of symptoms that can be treated.
Generally, the symptoms of Alzheimer's disease are divided into 3 main stages.
In the early stages, the main symptom of Alzheimer's disease is memory lapses.
For example, someone with early Alzheimer's disease may:
There are often signs of mood changes, such as increasing anxiety or agitation, or periods of confusion.
As Alzheimer's disease develops, memory problems will get worse.
Someone with the condition may find it increasingly difficult to remember the names of people they know and may struggle to recognise their family and friends.
Other symptoms may also develop, such as:
Some people also have some symptoms of vascular dementia
By this stage, someone with Alzheimer's disease usually needs support to help them with everyday living.
For example, they may need help eating, washing, getting dressed and using the toilet.
In the later stages of Alzheimer's disease, the symptoms become increasingly severe and can be distressing for the person with the condition, as well as their carers, friends and family.
Hallucinations and delusions may come and go over the course of the illness, but can get worse as the condition progresses.
Sometimes people with Alzheimer's disease can be violent, demanding and suspicious of those around them.
A number of other symptoms may also develop as Alzheimer's disease progresses, such as:
In the severe stages of Alzheimer's disease, people may need full-time care and assistance with eating, moving and personal care.
Read more about how Alzheimer's disease is treated.
If you're worried about your memory or think you may have dementia, it's a good idea to see your GP.
If you're worried about someone else's memory problems, encourage them to make an appointment and perhaps suggest that you go along with them.
Memory problems are not just caused by dementia – they can also be caused by depression, stress, medicines or other health problems.
Your GP can carry out some simple checks to try to find out what the cause may be, and they can refer you to a specialist for more tests if necessary.
Read more about diagnosing Alzheimer's disease.