We compared sedation levels in children following administration of intranasal dexmedetomidine. One hundred and sixteen children aged between 1 and 8 years were enrolled in this prospective, randomised trial. Children were assigned to receive either intranasal dexmedetomidine 1 μ−1 (Group 1) or 2 μ−1 (Group 2). Thirty-one (53%) patients from Group 1 and 38 (66%) patients from Group 2 were satisfactorily sedated at the time of anaesthetic induction. Logistic regression showed a significant interaction effect (p = 0.049), with the odds ratio between Group 2 over Group 1 estimated as 1.1 (95% CI 0.5–2.7) for the 1–4 year age group, and 10.5 (95% CI 1.4–80.2) for the 5–8 year age group. Both doses produced a similar level of satisfactory sedation in children aged 1–4 years, whereas 2 μ−1 resulted in a higher proportion of satisfactory sedation in children aged 5–8 years. There were no adverse haemodynamic effects. We conclude that intranasal dexmedetomidine in a premedication dose of 2 μ−1 resulted in excellent sedation in children.