6. Alternative drugs to antipsychotics
Antipsychotics are the drugs most often prescribed for people with dementia who have symptoms such as aggression and psychosis, but other drugs are available. Certain anti-dementia drugs, antidepressants and anticonvulsants may also be helpful in treating these symptoms. There is less evidence about whether some of these drugs work than there is for antipsychotics, but they also generally have less severe side effects.
There are two types of anti-dementia drugs that are routinely offered to people with Alzheimer’s disease, mixed dementia (Alzheimer's disease with vascular dementia) and sometimes dementia with Lewy bodies. The use of these drugs has been well studied in people with Alzheimer’s disease and they generally cause only minor side effects. They should not be offered to people with ‘pure’ vascular dementia or frontotemporal dementia as they haven’t been shown to bring any benefits. For more information see Drug treatments for Alzheimer’s disease.
One of these drugs, memantine, slows the progression of some symptoms (for example disorientation) in people with moderate to severe Alzheimer’s disease. There is some evidence that memantine also helps with aggression, agitation and delusions for people in this group.
The other anti-dementia drugs – donepezil, rivastigmine and galantamine – are known as ‘cholinesterase inhibitors’. They improve mental abilities (such as memory and concentration) in people with Alzheimer’s disease, mixed dementia (Alzheimer’s and vascular) and dementia with Lewy bodies. However, the effect of cholinesterase inhibitors on behavioural symptoms (such as aggression or agitation) is not clear.
Donepezil or rivastigmine may be tried for severe behavioural symptoms in people with dementia with Lewy bodies. This is because there is such a high risk of severe reactions to antipsychotic drugs for people with this type of dementia.
People with dementia with Lewy bodies often have hallucinations and delusions. Donepezil and rivastigmine successfully reduce these in many people with this type of dementia. NICE guidance recommends the use of a cholinesterase inhibitor for a person with dementia with Lewy bodies if psychotic symptoms are causing distress, or if challenging behaviour is posing a risk of physical harm.
Antidepressants such as sertraline, citalopram, mirtazapine and trazodone are widely prescribed for people with dementia who develop depression. Some recent trials have shown that common antidepressants do not work well in this group, but they may still be tried. For more information on depression see factsheet 444, Apathy, depression and anxiety.
Studies have shown that the antidepressant drugs sertraline and particularly citalopram may help to reduce agitation in people with dementia. Citalopram worked about as well in people with Alzheimer’s disease as an antipsychotic. However, the dose of citalopram that was needed to do this worsened people’s memory and caused side effects to the heart. Citalopram is not licensed for treating agitation and NICE do not recommend it for this purpose – even off-label – because of the side effects.
Anticonvulsant drugs are used to prevent fits in people with epilepsy. They are occasionally used for symptoms of aggression and agitation in people with dementia. The drug carbamazepine can be effective for the treatment of aggression, where other drugs have failed. However, carbamazepine has many side effects including sedation, falls, skin rashes, low sodium levels and blood disorders. It is often not a safe drug to use in someone with dementia.
There is now good evidence that another anticonvulsant called valproate should not be given to control agitation or aggression in people with dementia. Research is being done into the benefits of other anticonvulsants (for example, gabapentin) for people with dementia, but there is not enough evidence yet to say whether they work or not.