Imagine washing your hands up to 40 times a day, all because you are worried about germs.
You avoid touching anything that you deem dirty, and when you accidentally do, you get distressed and clean your hands until the skin becomes severely dry or even bleeds.
It may be hard to understand the beliefs that obsessive compulsive disorder (OCD) bring about.
This is a brain disorder that causes problems in information processing.
The repetitive actions, known as compulsions, can be taxing, yet the patient has to carry them out to ease his anxiety.
Both adults and children can have OCD, though younger patients are often unable to realise that their symptoms are abnormal.
So they are more unwilling to seek help, said Dr Adrian Loh, a visiting consultant at the department of child and adolescent psychiatry at the Institute of Mental Health (IMH).
It is not known what causes OCD.
What puts people at higher risk are an anxious temperament, a family history of OCD, a high number of stressors and insufficient levels of the brain chemical serotonin, said Ms Haanusia Prithivi Raj, a senior clinical psychologist at the same department at IMH.
One in 33 people suffers from OCD in his or her lifetime, according to the Singapore Mental Health Study.
Every year, the IMH Child Guidance Clinics treat 100 to 200 children and adolescents with OCD.
Younger patients often have compulsions, such as touching objects in a certain way.
"In many cases, they say it just feels right," said Dr Loh, adding that this can frustrate parents.
Some children with OCD may also suffer from anxiety disorders, attention deficit hyperactivity disorder or autism, he said.
Ms Haanusia shares tips for caregivers and schoolteachers of young people with OCD.
State in a matter-of-fact way that it is OCD that is making them do their rituals.
For example, you can say: "It seems that OCD wants you to wash your hands quite a bit. OCD is really being a pain today, isn't it?"
Do not blame your child by getting angry with his behaviour.
Articulate their distress in challenging thoughts, worries or urges that may not make sense.
Say things like: "It must be very hard when OCD is really loud in your head. OCD is making you feel anxious when you don't listen to it."
Do not attempt to stop or challenge your child's ritual if he has not learnt strategies to fight OCD.
These strategies include "exposure and response prevention", which involves the young person slowly facing his fear by repeatedly exposing him to it and waiting for his anxiety to pass without giving in to a compulsion.
When your child is doing the exposure tasks - the "homework" assigned for the child to practise facing his fears - such as touching the tap for the first time for someone who fears contamination, express your support, such as by saying: "You can fight OCD.
You are the boss, not OCD."
A teacher who observes signs of OCD in a young person should refer him to a school counsellor.
Support the young person's treatment. If the child or his family has given their consent, teachers could help by doing some exposure tasks with the patient in school.
Be patient and understand that the child is not trying to be difficult. Teachers should take note if the child becomes highly anxious in the classroom.
They may allow them to "sit out" their anxiety, discuss it, or take a short break. However, these options should first be discussed with the medical team so that teachers do not accidentally reinforce a young person's OCD.
Teachers should be alert about whether the young person with OCD is a victim of bullying.
This article was first published on September 1, 2015.
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