A leading psychiatrist says many adults with attention-deficit hyperactivity disorder (ADHD) are not getting the treatment they need.
Adults with ADHD can feel depressed when alone
Professor Philip Asherson, from London's Maudsley Hospital, wants sufferers to be recognised and treated.
ADHD is well-known in childhood, but estimates suggest up to 65% of sufferers are affected years later.
Adults with ADHD can experience depression, anxiety and impulsiveness, the British Journal of Psychiatry says.
Publicity around ADHD also means larger numbers of adults are recognising the key signs of the condition in themselves, and seeking help.
Professor Asherson said some adults might have already been misdiagnosed with a different mental health problem, and be receiving the wrong sort of treatment.
The use of stimulant drugs such as Ritalin is now commonplace in children, and he said this should become standard practice in adults as well.
"Medication, especially with stimulant drugs, is an effective means of reducing ADHD symptoms and behaviours in adulthood.
"For these reasons we strongly urge that appropriate drug treatment of ADHD should be a normal part of the therapeutic resources available within general adult psychiatry."
At present, there are relatively few NHS clinics aimed specifically at adult ADHD patients.
However, Professor Asherson argued doing nothing may be more costly.
"Adults with untreated ADHD use more healthcare resources because of smoking-related disorders, increased rates of serious accidents, and alcohol and drug misuse.
Further research is needed to quantify the contribution of ADHD to psychiatric disorders in adulthood."
'Dearth of facilities'
A recent survey of children with ADHD in Newham, in London, found although symptoms tended to decrease between the ages of seven and 17, the 17-year-olds showed a level of hyperactivity similar to that found in a group of normal seven-year-olds.
When the same people were seen again at the age of 26, they were found to have disabilities associated with high levels of psychiatric disorder, including feelings of restlessness, feeling depressed when inactive, depression, and difficulties sustaining relationships.
Dr Chris Steer, who treats paediatric ADHD in Fife, said that there was a 'dearth' of facilities aimed at older patients, which meant that patients entering adult life often lost the necessary support and treatment, even if they were still displaying ADHD symptoms.
He said: "We often keep looking after patients until they are 20 - I have some patients who are in their mid-20s.
"It's a very risky thing when you say to a patient: 'I'm sorry, we can't see you any more'."