Naphazoline is the common name for 2-(1-naphthylmethyl)-2-imidazoline hydrochloride. It is a sympathomimetic agent with marked alpha adrenergic activity. It is a vasoconstrictor with a rapid action in reducing swelling when applied to mucous membrane. It acts on alpha-receptors in the arterioles of the conjunctiva to produce constriction, resulting in decreased congestion. The imidazoline derivative naphazoline, an alpha(2)-adrenergic agonist, is used as non-prescription eye and nasal preparation because of its vasoconstrictive and decongestive properties. Especially in children, overdose and/or systemic side effects due to absorption can quickly cause severe central nervous system depression and cardiovascular adverse effects. In a 7-year-old boy was diagnosed a naphazoline intoxication by toxicological analysis. In general, physicians, pharmacists and the public should be educated about the toxicity of over-the-counter preparations.