Attention deficit hyperactivity disorder | Symptoms & Causes | Diagnosis

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Attention deficit hyperactivity disorder

What is Attention deficit hyperactivity disorder?

Attention-deficit/hyperactivity disorder (ADHD) refers to a constellation of inappropriate behaviors found in many children and adults. The essential feature of ADHD is a persistent pattern of inattention and/or hyperactivity-impulsivity. These features are more frequently displayed and more severe than typically observed in a child at a comparable level of development.

A child with ADHD may be unusually active and/or impulsive for their age and has trouble sustaining attention in various settings like at school, at home or at work. He often fails to give close attention to details or makes careless mistakes, does not wait for his term during sports, is talkative and does not sit quiet for long at places where he is expected to (for e.g., in a classroom). These behaviors may contribute to significant problems in social relationships and learning. For this reason, children with ADHD are sometimes seen as being "difficult" or as having behavior problems.

The symptoms should be inconsistent with developmental level and should have persisted for at least six months, to a degree that is maladaptive and inconsistent with developmental level and causes impairment.

Diagnosis and management of children with ADHD have been controversial but behavioraltherapy, medications and counseling are usually attempted.


Alcohol intake during pregnancy can cause fetal alcohol spectrum disorders which can include ADHD or symptoms like it. Children exposed to certain toxic substances, such as lead or polychlorinated biphenyls, may develop problems which resemble ADHD. Exposure to the organophosphate insecticides chlorpyrifos and dialkyl phosphate is associated with an increased risk; however, the evidence is not conclusive. Exposure to tobacco smoke during pregnancy can cause problems with central nervous system development and can increase the risk of ADHD.

Extreme premature birth, very low birth weight, and extreme neglect, abuse, or social deprivation also increase the risk as do certain infections during pregnancy, at birth, and in early childhood. These infections include, among others, various viruses (measles, varicella zoster encephalitis, rubella, enterovirus 71). There is an association between long term but not short term use of acetaminophen during pregnancy and ADHD. At least 30% of children with a traumatic brain injury later develop ADHD and about 5% of cases are due to brain damage.

Diagnosis & Tests

Associated conditions that should be screened for include anxiety, depression, oppositional defiant disorder, conduct disorder, and learning and language disorders. Other conditions that should be considered are other neurodevelopmental disorders, tics, and sleep apnea.

Prevention & Risk Factors

Preventions impede the emergence of a disorder or injury, and typically take the form of public health initiatives, such as the use of seatbelts in cars, inoculations for viral diseases, or promoting exercise and healthy diets for preventing obesity and cardiovascular disease. For ADHD and other neurodevelopmental disorders, prevention initiatives include programs that promote maternal health during pregnancy, such as warnings against alcohol and cigarette use, as well as initiatives to reduce environmental toxins, such as lead and mercury. These initiatives will not eradicate ADHD, but they may lower incidence rates.

Treatments & Therapies

Treatment for attention deficit hyperactivity disorder (ADHD) can help relieve the symptoms and make the condition much less of a problem in day-to-day life.
ADHD can be treated using medication or therapy, but a combination of both is often best.
Treatment is usually arranged by a specialist, such as a paediatrician or psychiatrist, although the condition may be monitored by your GP.

There are 5 types of medication licensed for the treatment of ADHD:

  • methylphenidate
  • dexamfetamine
  • lisdexamfetamine
  • atomoxetine
  • guanfacine

These medications are not a permanent cure for ADHD but may help someone with the condition concentrate better, be less impulsive, feel calmer, and learn and practise new skills.

Some medications need to be taken every day, but some can be taken just on school days. Treatment breaks are occasionally recommended to assess whether the medication is still needed.