Johnny is 6 years old. His teacher has expressed concerns about him at the parent and teacher meeting. Johnny is often found daydreaming in class and is unable to keep up with his homework. Worryingly, Johnny frequently gets into arguments with his classmates.

Johnny was referred for a paediatric assessment and was subsequently diagnosed with Attention Deficit Hyperactivity Disorder ("ADHD").

a) In accordance with the Diagnostic and Statistical Manual of Mental Disorders 5 ("DSM-5"), what are the core symptoms of ADHD? (3 marks)

b) What are the stimulant and non-stimulant pharmacological options available in Hong Kong to Johnny? (3 marks)

c) Which pharmacological treatment would you recommend to Johnny? Discuss your selected option with reference to the pharmacokinetic profile, pharmacology, efficacy, safety profile and adherence (compliance) issues. (12 marks)

d) Johnny's parents decide not to put him on medication, what other non-pharmacological options are available? (2 marks)