Design A prospective observational study over 1 year.

Setting A District General Hospital, and Child and Adolescent Mental Health Department.

Patients Children aged 8–18 years living in the catchment area of a district hospital service with any type of unexplained hallucinations or illusions associated with or without an established diagnosis of migraine.

Results The study identified nine children with a combination of migraine and a variety of hallucinations and illusions, including illusions of size, time, colour, body shape, movement and visual and auditory hallucination. An average of 10 symptoms (range 7–15) were reported.

Interventions None.

Main outcome measure None.

Conclusions It is important to recognise these symptoms to enable appropriate history taking and diagnosis. These symptoms are common and currently seem to go unrecognised and may pose diagnostic difficulties if onset is before typical migraine headaches occur.