logo

Olanzapine and Autism Ranking: Mildly Hazardous Limited positive evidence

Anti-psychotic, olanzapine

Olanzapine is an antipsychotic drug used to treat the symptoms of schizophrenia and bipolar disorder.

It is sold under a variety of brand names including Zyprexa, Zolafren and Zydis.

The exact mechanism by which olanzapine works is unknown but some people believe it can be used to change the levels of dopamine and serotonin in the central nervous system.

It is sometimes used to treat problem behaviours in people on the autism spectrum, including hyperactivity, aggression, and self-injurious behaviours.

Our Opinion

There is some very limited research evidence to suggest that olanzapine may be beneficial for the short term treatment of significant problems faced by people on the autism spectrum, including hyperactivity, aggression, and self-injurious behaviours.

However there are many potential side effects, especially significant weight gain in all who take it, as well as increased appetite and increased drowsiness in some.  The implications of these side effects are unknown.  For these reasons, it is important to use the lowest effective dose

There is probably more weight gain with olanzapine than with other atypical antipsychotics. It is therefore not the first choice and caution is needed.

Further research should be undertaken into the use of olanzapine and other antipsychotics for the treatment of specific, severe symptoms, as each has a different side effect profile, and so might suit some people better.

Disclaimer

Please read our Disclaimer on Autism Interventions


Aims and Claims

Aims

The exact mechanism by which olanzapine works is unknown but some people believe it can be used to change the levels of dopamine and serotonin in the central nervous system. They believe that this will have beneficial effects, including a reduction in hyperactivity, aggression, and repetitive behaviours.

Claims

There have been various claims made for olanzapine as a treatment for people on the autism spectrum.  For example,

  • Fidoa A., Al-Saadb S. (2008) reported ‘The study shows that olanzapine treatment can be beneficial in alleviating some behavioral symptoms (irritability, hyperactivity/noncompliance and lethargy/withdrawal) associated with autism’
  • Hollander E. et al. (2006) reported ‘Olanzapine may be a promising treatment for improving global functioning of PDDs,’
  • Kemner C. et al. (2002) reported ‘significant improvement on three subscales of the Aberrant Behavior Checklist (Irritability, Hyperactivity, and Excessive Speech) and the TARGET i.e. communication’
  • Potenza M. et al. (1999) reported ‘Significant improvements in overall symptoms of autism, motor restlessness or hyperactivity, social relatedness, affectual reactions, sensory responses, language usage, self-injurious behavior, aggression, irritability or anger, anxiety, and depression were observed. Significant changes in repetitive behaviors were not observed for the group.’
  • Stavrakaki C.,  Antochi R.,  Emery P.C. (2004) reported 'All patients showed clinically significant improvements in behavioural symptoms, measured both clinically using the CGI scale and by the GAF scale.'
  • Tan Q. et al. (2006) reported 'Modified electroconvulsive treatment together with olanzapine caused a dramatic clinical improvement [in catatonia].'

Audience

According to American Society of Health-System Pharmacists (2013)

“Olanzapine is used to treat the symptoms of schizophrenia  in adults and teenagers 13 years of age and older. It is also used to treat bipolar disorder in adults and teenagers 13 years of age and older.”

Olanzapine is also sometimes used to treat people on the autism spectrum who also have specific, severe symptoms including mental health problems and behaviour problems.

Key Features

Olanzapine is a type of atypical antipsychotic drug, which is sold under a variety of brand names including Zyprexa, Zydis and Zolafren.

Antipsychotic drugs are used to treat the symptoms of a range of conditions including schizophrenia and bipolar disorder. They work by changing the activity of certain natural substances in the brain, although the exact mechanism is unclear.  Atypical anti-psychotic drugs are newer than older, typical anti-psychotic drugs and are believed to be better tolerated, with less side-effects.

Olanzapine comes in a variety of forms, including as a tablet and as an intra-muscular injection.

You will need to consult a psychiatrist, GP, or other suitably qualified medical practitioner, for the latest information on specific formulations and doses

Cost and Time

Cost

Olanzapine is more expensive than older antipsychotic drugs, such as haloperidol or chlorpromazine.  However within the UK, it is available free of charge via the National Health Service.

Time

In the UK medications such as olanzapine are available free of charge to patients within the NHS. In other countries the costs may be covered by some insurance policies.

Olanzapine is usually taken once a day with or without food at around the same time every day, although it is also available as a depot (long lasting) injection.

Parental involvement in the use of olanzapine is minimal since the person on the autism spectrum usually takes it once a day.

Risks and Safety

Hazards

Olanzapine has been shown to produce a number of side effects in some people.  For example, according to the American Society of Health-System Pharmacists  (2013) it can cause

  • drowsiness
  • dizziness
  • restlessness
  • unusual behavior
  • depression
  • difficulty falling asleep or staying asleep
  • weakness
  • difficulty walking
  • constipation
  • weight gain
  • dry mouth
  • pain in arms, legs, back, or joints

More seriously, it can also cause

  • seizures
  • changes in vision
  • swelling of the arms, hands, feet, ankles, or lower legs
  • unusual movements of your face or body that you cannot control
  • fever
  • very stiff muscles
  • excess sweating
  • fast or irregular heartbeat
  • rash
  • hives
  • difficulty breathing or swallowing

In addition

‘Studies have shown that older adults with dementia … who take antipsychotics (medications for mental illness) such as olanzapine have an increased chance of death during treatment.’

Please note that olanzapine can, if taken with certain other drugs, increase, decrease or alter the effect of those other drugs.

Research has shown that olanzapine can produce some side effects in people with autism spectrum disorders, including

  • significant weight gain
  • increased appetite
  • drowsiness

Contraindications

Olanzapine should be used cautiously with people who are

  • using a number of other medications including anticonvulsants, antidepressants, antihistamines, sedatives, sleeping pills and tranquillisers
  • use or have ever used street drugs or have overused prescription medications
  • have or have ever had a number of other conditions including stroke, heart disease, seizures, breast cancer, high or low blood pressure, liver or prostate disease, glaucoma or diabetes
  • are pregnant, breast-feeding or planning to have surgery

Suppliers and Availability

Olanzapine is a powerful drug with many potential side effects and contraindications. For this reason it should only be obtained on prescription from either a psychiatrist, or from a GP on the advice / recommendation of a psychiatrist.

History

Olanzapine was developed and is currently marketed by the pharmaceutical company Eli Lilly and Company. It was approved by the United States Food and Drug Administration (FDA) in 1996 for the treatment of schizophrenia, acute mania in bipolar disorder, agitation associated with schizophrenia and bipolar disorder, and as maintenance treatment in bipolar disorder and psychotic depression.

Current Research

We have identified nine scientific studies of olanzapine used to treat people with autistic spectrum disorders published in peer-reviewed journals.  The studies included more than 100 individuals, aged from six years old to adult.

  • Seven of the studies (Fidoa and Al-Saadb, 2008; Hollander et al, 2006; Kemner et al, 2002; Malone et al, 2001; Potenza et al, 1999; Stavrakaki, Antochi and Emery, 2004; Tan et al. 2006) found that olanzapine was effective and well tolerated for the treatment of problems such as tantrums, aggression, or self-injurious behaviour in children and/or adults with autism spectrum disorders, although one study (Tan et al. 2006) reported that olanzapine was only effective in the treatment of catatonia when combined with electro-convulsive therapy.
  • Two studies (Hollander et al., 2006; Stavrakaki, Antochi and Emery, 2004) went further, stating that olanzapine leads to improvements in some, but not all, symptomatic behavioural symptoms in children and/or adults with autism spectrum disorders.
  • Four studies (Hollander et al., 2006; Kemner et al 2002; Malone et al, 2001; Potenza  et al, 1999) reported significant side effects including weight gain, increased appetite and increased drowsiness.

Status Research

There are a number of limitations to all of the research studies published to date. For example

  • Some of the studies – such as such Malek-Ahmadi and Simonds (1998), Tan et al. (2006) and Horrigan et al. (1997) – were case studies or case series and had either one or two participants
  • Some of the studies – such as Potenza et al. (1999), Kemner et al. (2002) and Fido and Al-Saadb (2008) – were open label i.e. non-blinded trials, and/or had no comparison control group.
  • One of the randomised controlled studies – Malone et al. (2001) – was non-blinded and had only 12 participants. The randomised controlled study that was blinded - Hollander et al. (2006) - had only 11 participants

For a comprehensive list of potential flaws in research studies, please see Why some research studies are flawed

Ongoing Research

This page provides details of ongoing research into olanzapine and people on the autism spectrum.

If you know of any other trials we should include please email info@researchautism.net with the details. Thank you.

Future Research

Summary of Existing Research

There is some evidence that olanzapine may be beneficial for the treatment of various problems faced by people with autism, including hyperactivity, aggression, and self-injurious behaviours.

There is almost no research evidence to suggest that aripiprazole may be beneficial for the treatment of these behaviours in adults on the autism spectrum.

There are a few anecdotal reports which suggest that aripiprazole may be beneficial for some children and/or adults on the autism spectrum.

There is some research evidence of significant side effects of olanzapine in some children and young people on the autism spectrum. Those side effects may include weight gain, increased appetite and increased drowsiness.

There is also some research which suggests that some antipsychotics, such as olanzapine, can actually increase hyperactivity through akathisia (a movement disorder characterised by a feeling of inner restlessness and a compelling need to be in constant motion).

As always a judgement should be made by the clinical team as to whether the symptoms or behaviours arise from a reaction of the autistic person to stressors in the social or wider environment or whether they related to an underlying psychiatric disorder in the true sense. The treatment approach will differ accordingly with the former less likely to respond to psychotropic drug-based interventions alone.

Recommendations for Future Research

Further, large-scale, randomised, double-blind trials of the effects of olanzapine should be carried out on individuals on the autism spectrum to determine their effectiveness and safety. 

These studies should investigate issues such as

  • The optimal dosage and length of treatment for different individuals on the autism spectrum including adults
  • Comparison of olanzapine with other medications, including with other antipsychotics, such as aripiprazole and risperidone.

Studies and Trials

This section provides details of scientific studies into the effectiveness of this intervention for people with autism which have been published in English-language, peer-reviewed journals. If you know of any other studies we should include please email info@researchautism.net with the details. Thank you.

If you are a UK resident you may be able to obtain full copies of some of the items listed here from your local public library, your college library, or the National Autistic Society's Information. Centre. You may also be able to obtain copies from the publisher of the items.

Other Reading

This section provides details of other publications on this topic. If you know of any other publications we should include please email info@researchautism.net with the details. Thank you.

Please note that we are unable to supply publications unless we are listed as the publisher. However, if you are a UK resident you may be able to obtain them from your local public library, your college library or direct from the publisher.

Personal Accounts

We have been unable to identify any anecdotal reports for the use of olanzapine to treat problems in people on the autism spectrum. If you are aware of any please email info@researchautism.net with the details. Thank you.

Additional Information

NICE Guidance

The National Institute for Health Care Excellence has provided clinical guidance on the use of pharmacological interventions (such as olanzapine) for behaviour that challenges in children and young people on the autism spectrum.

 

Updated
19 Dec 2017
Last Review
01 Feb 2016
Next Review
01 Feb 2019