Dexmedetomidine is a selective a-2 adrenergic agonist that provides sedative and analgesic effects. Intranasal dexmedetomidine has a slower and gradual onset compared to intravenous injection , with low incidence of nasal discomfort. Dexmedetomidine was tested at various doses and modes of administration, as well as different types of surgery and co-anesthetic drugs, as a single injection or continuous infusion. The authors have not agreed on the ideal clinical dose. The hypothesis is that intranasal dexmedetomidine 3mcg /kg will decrease the incidence of emergence agitation after strabismus surgery than dexmedetomidine 2 mcg/kg