It can be difficult for doctors to tell if someone has dementia, especially in the early stages.

There's no test that can tell someone that they definitely have Alzheimer's or another type of dementia. But there are tests that can help doctors decide whether it's likely that someone has one of these conditions.

The early signs of dementia are easy to miss. And there's no way of knowing exactly when it starts, unless someone develops dementia due to a stroke. Scientists are trying to find ways of spotting dementia early on. It's helpful if people with dementia can plan for the future while they can still take part in decisions.

Seeing a GP

If you think that someone in your family might have Alzheimer's or another type of dementia, you should make sure they see their GP. You may find that they don't want to see a doctor about their symptoms. But you might be able to persuade them to go for a physical check-up or for help with a specific problem, such as not being able to get to sleep.

When doctors first see someone who gets confused or has problems with their memory, they need to rule out other things that can cause these symptoms.

Depression and other conditions can cause symptoms of dementia. It's important that other conditions are spotted and treated if possible. ^[14]

Some people may have two types of dementia at the same time. For example, someone may have Alzheimer's and vascular dementia. This can make it difficult to accurately diagnose what is causing their symptoms. ^[29]

When GPs first see someone who might have dementia, they usually: ^[30]

• Ask about the person's medical history

• Examine the person physically and take samples of their blood and urine to rule out other diseases

• Carry out some tests to see how well the person's memory, language skills and reasoning abilities are working.

Seeing a specialist

Doctors have guidelines about how to treat someone who may have Alzheimer's disease. These say that if a GP thinks someone may have Alzheimer's, he or she should refer the person to a doctor specialising in dementia for a diagnosis. ^[31] This might be a neurologist, a geriatrician, a psychiatrist or a psychogeriatrician.

People with other types of dementia will usually be referred to see a specialist too. But there are no guidelines that say this should definitely happen. If your GP has not suggested a referral and you would like to see a specialist, you can ask for one. ^[30]

It is more important today than it was in the past to find out what type of dementia someone has. This is because there are now drugs that can treat certain dementias. Most of these drugs work best in the early stages of the condition. So, it's important to get a clear diagnosis early on. A specialist has more experience than a GP in diagnosing and treating people with dementia and also has access to more specialised tests.