2. The multi-centre Randomised Clinical Trial will determine the safety and efficacy of oral olanzapine, in comparison with conventional medicines (haloperidol or diazepam) in a three-arm comparison for the sedation of acutely agitated patients in AEDs. Specifically, we aim to determine if administration of oral olanzapine (a)is more effective than sedation with oral haloperidol or oral diazepam alone; (b)is safer than sedation with comparison arms; (c)decreases the amount of subsequent redosing or alternative drugs required; (d)is more favourable than the haloperidol and diazepam arms with respect to safety, efficacy and adverse events.