There is a large body of research showing that there is a much higher prevalence of psychiatric disorders in children and adolescents with intellectual disability (ID) than in those without. Emerson and Hatton (2007) found that the risk for a mental health problem for children with intellectual disability (ID) was higher but these children are also more likely to live in poverty, have a reduced social network and have more difficult family circumstances which are factors known to increase risk of developing mental health problems. The current research aims to identify any association between prescription of psychotropic medication and bio-psycho-social factors. A cross sectional analysis of prescribing patterns in children open to the Child and Adolescent Intellectual Disability and Autism service from February 2010 to June 2010 was carried out. Information was collected from all 149 cases open to this team during this period. Prescription of psychotropic medication is associated with biological factors, such as age, diagnosis, degree of intellectual disability; behavioural factors such as self-injury, causing injury to others; and social factors like deprivation and unemployment. Prescription of psychotropic medication in children and adolescents with intellectual disability in specialist medical services is high, with anti-attention deficit hyperactivity disorder (ADHD) medication being the most prescribed medication, followed by antipsychotics. The rates of prescription were associated with a combination of biological, behavioural and social factors.