Attention Deficit Hyperactivity Disorder (ADHD) - Symptoms & Causes

What is ADHD?

ADHD is a mental disorder that affects the behaviour or development of young children. Children suffering from ADHD typically show the following signs before they turn 7 years old:

  • Inattention
  • Overactivity
  • Impulsiveness

Many children with ADHD can’t explain why they might feel out of control or very lonely. This condition is more common in boys than girls.

Types of ADHD

There are 3 types of ADHD:

  • Predominantly inattentive, where the child is mostly unable to hold attention.
  • Predominantly hyperactive or impulsive, where the child's behaviour tends to be hyperactive or impulsive.
  • Combined, where the child displays a mix of inattentive and hyperactive or impulsive symptoms.

What are the symptoms of ADHD?

Children with ADHD tend to face the following challenges due to their difficulties in paying attention or regulating their hyperactive or impulsive behaviours:

  • Academic
    • Learning disabilities
    • Not doing well in school
  • Cognitive
    • Poor problem-solving abilities
    • Inability to understand the consequences of misbehaving
    • Talking to themselves in a childish way (relative to their age)
  • Emotional
    • Depression
    • Inability to control their emotions
    • Unpredictable moods
  • Social
    • Aggressiveness
    • Inability to make friends
    • Inability to follow instructions
    • Lying, stealing and high-risk tendencies
    • Lack of self-control
    • Poor social skills

What causes ADHD?

Researchers are still working to understand the exact cause of ADHD. However, a combination of factors is found to be related to ADHD. These include:

  • Head injury
  • Brain infection
  • Lead poisoning
  • Maternal drug use
  • Family history of ADHD
  • High blood pressure and infections during pregnancy
  • Neurological imbalances in the brain, affecting areas that control focusing, planning and organisation

What are the risk factors for ADHD?

Risk factors for ADHD may include:

  • Epilepsy
  • Premature birth (before the 37th week of pregnancy)
  • Exposure to environmental toxins, such as lead
  • Family history of ADHD or another mental health disorder
  • Brain damage, either in the womb or after a severe head injury later in life

Children with ADHD are more prone to the following struggles:

  • Suffering from low self-esteem
  • Being more prone to accidents and injuries compared to their peers
  • Being socially awkward and having trouble gaining acceptance by peers and adults
  • Falling behind in class, which can result in poor academic performance and judgement by other children and adults

Children with ADHD are also more likely than others to have the following co-existing conditions:

  • Epilepsy
  • Depression
  • Dyslexia and other types of learning difficulties
  • Anxiety disorder, causing your child to often worry and feel nervous
  • Autistic spectrum disorder, which affects how your child perceives and socialises with other people
  • Conduct disorder, causing antisocial behaviour such as stealing, fighting, vandalising and harming people or animals
  • Tourette's syndrome, where your child involuntarily makes unwanted noises and repetitive movements
  • Sleep problems, such as having trouble falling asleep and irregular sleeping patterns
  • Substance use disorders, including drugs, alcohol and smoking
  • Mood disorders such as bipolar disorder
  • Oppositional defiant disorder

How do you prevent ADHD?

Methods to prevent ADHD are still unknown by researchers. However, you can reduce your child's risks of ADHD by:

  • Avoiding alcohol, drug abuse and cigarettes during pregnancy
  • Limiting your child's exposure to pollutants and toxins

Early detection and intervention can help to reduce the severity of your child's symptoms and support their healthy growth and development.

This page has been reviewed by our medical content reviewers.

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