Antipsychotic drugs may be prescribed for people with dementia who develop changes such as aggression and psychosis. However this is usually only after other drugs have been tried such as anti-depressant, anti-dementia and anticonvulsant drugs.
Antipsychotic drugs may be prescribed for people with dementia who develop changes such as aggression and psychosis, but usually only after other drugs have been tried.
Certain antidepressants, anti-dementia drugs and anticonvulsants may be helpful in treating these changes. There is less evidence about whether some of these drugs work than there is for antipsychotics, but they generally have less severe side effects.
Antidepressants such as sertraline, citalopram, mirtazapine and trazodone are widely prescribed for people with dementia who develop changes in mood and behaviour.
There is some evidence that they may help to reduce agitation – particularly citalopram. However, the dose of citalopram needed to reduce agitation may cause severe side effects, including a higher risk of falls and a dangerously irregular heartbeat. For this reason, citalopram is not licensed for treating agitation.
However, some doctors may prescribe citalopram in lower doses if they think that the person’s agitation may partly be caused by anxiety or depression.
The main type of drugs used to treat problems with memory and thinking are acetylcholinesterase (AChE) inhibitors.
AChE inhibitors include donepezil, rivastigmine and galantamine. They are routinely offered to people with Alzheimer’s disease, dementia with Lewy bodies, Parkinson’s disease dementia, or any mixed dementia that includes one of these types (for example, Alzheimer’s disease with vascular dementia). They are normally prescribed soon after diagnosis and continued throughout the course of the person’s dementia.
There is some evidence that these drugs may also slightly reduce agitation in people with moderate-to-severe Alzheimer’s disease. They may also help to reduce hallucinations and delusions in people with Lewy body dementia. However, they are rarely prescribed specifically for these purposes because most people with these types of dementia will already be taking them anyway.
Another drug used to treat problems with memory and thinking is memantine. This tends to be used in addition to an AChE inhibitor as dementia progresses.
Memantine is sometimes prescribed to reduce levels of aggression or psychosis and has fewer risks and side effects than antipsychotic drugs. It should not be prescribed if the person has vascular dementia.
To find out more read our information on drug treatments for Alzheimer’s disease.
Anticonvulsants are used to prevent fits in people with epilepsy. They are occasionally used for aggression and agitation in people with dementia. However, there is little evidence that they are effective, and they have a wide range of side effects, so they are not recommended for this purpose.
Antipsychotic drugs are used to treat people who are experiencing severe agitation, aggression or distress from psychotic symptoms, such as hallucinations and delusions. They tend to be used only as a last resort, such as when the person, or those around them, are at immediate risk of harm.
For some people, antipsychotics can help to reduce the frequency or intensity of these changes. However, they also have serious risks and side effects, which the doctor must consider when deciding whether to prescribe them.
The first prescription of an antipsychotic should only be done by a specialist doctor. This is usually an old-age psychiatrist, geriatrician or GP with a special interest in dementia.
There are several antipsychotic drugs that may be used. Each one has slightly different effects on the brain and has its own potential risks and side effects.
The drug with the most evidence to support its use in dementia is risperidone. It is licensed for short-term (up to six weeks) treatment of persistent aggression in people with moderate-to-severe Alzheimer’s disease when there is risk of harm to the person or others. However, this is only if non-drug approaches have already been tried without success.
An older antipsychotic called haloperidol is licensed for use in people with Alzheimer’s disease or vascular dementia. However, most doctors consider its risks and side effects in people with dementia to be too severe. It tends to be used only in emergencies as a last resort.
Other antipsychotic drugs prescribed for people with dementia are done so ‘off-label’. This means that the doctor can prescribe them if they have good reason to do so, and provided they follow guidance set out by the General Medical Council.
A doctor may choose to prescribe an off-label antipsychotic drug when it offers a better balance of benefits and risks for an individual patient. For example, risperidone may be effective in people with dementia, but it also increases the risk of having a stroke. So if a person has already had a stroke it might be safer to prescribe an off-label drug that doesn’t carry this risk, even though it might be less effective.
The off-label antipsychotics most often used for patients with dementia are:
Antipsychotic drug treatments should be reviewed after six or 12 weeks, or both.
When the prescription of an antipsychotic is reviewed, the doctor may suggest stopping the drug in one go (for people taking a low dose of antipsychotic) or a more gradual reduction (for people on a higher dose) known as ‘tapering’. In either case, the effects on the person’s behavioural and psychological changes should be closely monitored. If they seem to be getting worse, it may be necessary to restart or increase the dose again.
If the person had a pre-existing mental health condition before they developed dementia and this was managed with antipsychotic drugs, they should continue to take them as prescribed by their psychiatrist.
Some antipsychotics can have a small but significant beneficial effect on agitation, aggression and, to a lesser extent, psychosis in people with Alzheimer’s disease. Improvements are normally only seen once these drugs have been taken for several weeks.
Antipsychotic drugs may be prescribed for people with Alzheimer’s disease, vascular dementia or mixed dementia (which is usually a combination of these two).
If a person with dementia with Lewy bodies or Parkinson’s disease dementia is prescribed an antipsychotic drug, it should be done with the utmost care, under constant supervision and with regular review. This is because people with these types of dementia, who often have visual hallucinations, are at particular risk of severe negative reactions to most antipsychotics.
The doctor is likely to choose a drug with the least side effects, but they will only be able to use very small doses. This is unlikely to have much effect on agitation and psychosis.