An “alarming” number of pre-school children are being prescribed drugs to treat hyperactivity – contrary to medical guidelines that say they should not be used on children under six – because overstretched health workers go straight to medication rather than offering psychological interventions.

More than a fifth of educational psychologists say they know of preschool children who are being given medication such as Ritalin even though the National Institute for Health and Clinical Excellence (Nice) recommends psychological interventions should be tried first.

The survey, which aimed to investigate the medicalisation of childhood behaviour, also found there was an “intolerance of difference”, so children not conforming to the norm were increasingly being seen as having something wrong with them.

One educational psychologist who took part in the study, which was carried out by the University College London Institute of Education (IoE) and the British Psychological Society, wrote: “Our biggest difficulty is that children’s and adolescent mental health services and paediatric teams are so short-staffed they go straight to medication and completely ignore Nice guidance.”

Ritalin, which is the most commonly used trade name for methylphenidate, is a central nervous system stimulant used to treat attention deficit disorder (ADD) and attention deficit hyperactivity disorder (ADHD).

The Nice guidelines, which were amended in 2013, state: “Parent-training/ education programmes are the first-line treatment for parents or carers of pre-school children … Drug treatment is not recommended for pre-school children with ADHD.”

The findings are part of a survey of 136 educational psychologists from 70 local authorities across the UK, seeking their views on the assessment, diagnosis and treatment of ADHD.

The report found that medication was seen as the main solution in the treatment of ADHD. “Medication was felt to be the predominant form of treatment for ADHD despite Nice guidelines that psychological interventions should be implemented first,” the report said.

“Multiple systemic factors” were creating a “pressure for increasing rates of diagnosis and medication”.

The survey, which will be formally published next year, said there was an “urgent need to examine local policies regarding the effective prevention and intervention in cases of pre-school behavioural, emotional and social difficulties”.

Vivian Hill, director of professional educational psychology training at the IoE, who conducted the research with Horatio Turner of UCL, said: “It is very alarming to discover that terribly young children who often have not had access to alternative treatments are being put on medication.

“It is almost certainly to do with the fact that the whole of children’s mental health services is incredibly underfunded. It’s quick and easy – one off the waiting list, one intervention in place.

“To work with a child or a young person and their family over time is much more costly, but much safer and likely to have much better results. Medication has a short-term impact. It will not make the difference long-term.”

Educational psychologists who took part in the survey said “intolerance of difference” affected the way adults viewed children’s learning and behaviour. One wrote: “There is an increasingly prevalent view in society that people who do not fit a particular environment must have something wrong with them.”

The report said “within-child” factors were emphasised too often, rather than environmental factors, “due to families and schools wishing to abdicate responsibility for children’s behaviour and systemic failings in current diagnostic procedures”. One participant said: “It’s an easy explanation, which is convenient and comforting and absolves everyone of blame by locating the problem within the child.”

Educational psychologists said they were frustrated by factors that limited their ability to care effectively for children with ADHD. “Usually when [we] get involved the die is cast and is predominantly problem-focused, so much so that the only perceivable solution is medication,” one wrote.

The report concluded that educational psychologists should be involved in developing a broader understanding of contextual perspectives of ADHD among families and recommended establishing a multi-agency approach for its assessment and treatment.

One EP said: “My local authority has a behaviour pathway that includes ADHD.” Following its introduction one of the survey participants said that behavioural observation by an educational psychologist led to a significant fall in the diagnosis and medication of ADHD.

A Department of Health spokesman said: “Prescribing decisions are for doctors to make, but there are clear independent guidelines for the treatment of ADHD, which only recommend the use of drugs in severe cases and as part of a comprehensive treatment plan.

“Children’s mental health is a key priority, which is why we’ve formed a taskforce to look at how we can provide the best possible care and have invested £54m in improving access to psychological treatments.”