Antipsychotic Use in Intellectually Disabled Adults
September 1, 2017   

In a new study conducted by the Centre for Addiction and Mental Health (CAMH) and Institute for Clinical Evaluative Sciences (ICES), researchers have found that antipsychotic medication is frequently being prescribed to individuals with intellectual and developmental disabilities (IDD), often without a psychiatric diagnosis. Antipsychotics can be prescribed to adults with IDD as a method of managing behavioral challenges, sometimes without a comprehensive assessment of the underlying contributors to such behaviors, despite the evidence supporting such use being inconclusive. According to guidelines1-4, antipsychotics should not be used as a first line treatment for behavior challenges.

Study Finds Antipsychotics Commonly Prescribed to Adults with IDD

Lunsky Y et al. recently published a population-based study that examined the health care of 51,881 adults with intellectual and developmental disabilities (IDD) over a per six-year period. Results showed Analysis showed that among the 51,881 adults with IDD, 39.2% (N = 20,316) were dispensed at least one antipsychotic during the six-year period. Of those antipsychotic users, 71.1% (N = 14,453) had a documented psychiatric diagnosis in the 2 years preceding the prescription date; and only 39.9% (N = 8,115) had a major mental illness (e.g. schizophrenia, bipolar disorder, or major depressive disorder). Most prescriptions were for atypical antipsychotics (84.1%), with the most commonly dispensed medications being oral quetiapine (29.2%), followed by oral risperidone (25.0%), and oral olanzapine (21.8%). Compared with those with a psychiatric diagnosis, antipsychotic users without a psychiatric diagnosis tended to be slightly older (average age 41.03 years versus 43.52 years), of higher socioeconomic status, and were less likely to reside in urban locations.

A greater percentage of individuals living in a group home setting reported use of antipsychotics compared to those living independently. A total of 7,219 of the 51,881 adults with IDD resided in a group home setting. Among those adults, 56.4% (N = 4,073) were prescribed an antipsychotic, and of those, 42.9% (N = 1,748) had no documented psychiatric diagnosis. The most commonly dispensed medications were oral risperidone (31.2%), followed by oral quetiapine (26.5%)

Major Mental Illness: schizophrenia, non-schizophrenia psychotic disorder, bipolar disorder or major depressive disorder;
Other Psychiatric Diagnosis: other depressive disorders, anxiety, somatoform, dissociative, psychosomatic, personality disorders, adjustment disorders, disorders of conduct or impulsivity.

Study Reference: Lunsky Y, Khuu W, Tadrous M, Vigod S, Cobigo V, Gomes T. Antipsychotic Use With and Without Comorbid Psychiatric Diagnosis Among Adults with Intellectual and Developmental Disabilities. Can J Psychiatry. 2017; Epub Ahead of Print
>> Lunsky Y et al. Can J Psychiatry. 2017; Epub Ahead of Print

Behavioral and psychiatric disorders are common in individuals with intellectual disabilities. Diagnostic challenges in this population may contribute to an under recognition of psychiatric illness. When psychiatric symptoms or behavioral problems cause significant distress and impairment, it may be necessary to implement psychopharmacological treatment; however, the evidence base for such treatments, specifically in patients with intellectual and developmental disabilities, is lacking. Several practice guidelines1-4 have been published to guide clinicians regarding the use of antipsychotic medications for adults with IDD for psychiatric and/or significant behavior concerns. Below are some of the situations under which the clinicians may consider the use of antipsychotic medication to manage problem behavior:

  • All non-medication management or other interventions alone do not produce change within an agreed time
  • Severe risk/ evidence of harm/distress to self
  • Severe risk/ evidence of harm/distress to others or property
  • High frequency/severity of problem behaviors
  • To treat an underlying psychiatric disorder or anxiety
  • Treatment for any coexisting mental or physical health problem has not led to a reduction in the behavior
  • To calm the person to enable implementation of non-medication based interventions

The exact situation under which medication and/ or non-medication based management strategies should be implemented will depend on individual circumstances. Antipsychotic prescribing can be problematic for this population due to the potential for adverse effects such as the increased risk for metabolic complications. Furthermore, adults with IDD may have difficulties in providing informed medical consent and reporting unfavorable side effects should they arise.

     Additional Resources:

MPP Drills:
The Case: 28-Year-Old Woman With Autism Needs Reassessment of Her Medications


    2. National Institute for Health and Care Excellence. Mental health problems in people with learning disabilities: prevention, assessment and management. NICE guideline. 2016. Available from:

    3. Royal College of Psychiatrists, Faculty of psychiatry of intellectual disability. Psychotropic drug prescribing for people with intellectual disability, mental health problems and/or behaviours that challenge: practice guidelines. 2016. Available from:

    4. Sullivan WF, Berg JM, Bradley E, . Primary care of adults with developmental disabilities: Canadian consensus guidelines. Can Fam Physician. 2011;57(5):541–553, e153–e168. Available from: