The causes for airway obstruction include foreign body aspiration, congenital structural abnormalities of the airway, infection, etc. And the potential causes of acute respiratory distress contain many situations, like hyperventilation, vasodepressor syncope, asthma, etc. A major factor that leads to the exacerbation of respiratory disorders is undue stress, either physiologic or psychologic. Psychologic stress in dentistry is the primary factor in the exacerbation of preexisting medical problems. Adequate pretreatment medical and dental evaluation of the prospective patient can often prevent respiratory problems from developing. The dentist can modify patient management to minimize the risk of exacerbating these conditions. When dental anxiety is a major factor, the use of psychosedative procedures and other stress-reduction techniques should also be considered. This is the report of a children case of airway obstruction and respiratory distress owing to sedation complication by use of Chloral hydrate and Ketamine before extraction of the mesiodens in a patient with bronchial asthma and tonsillar hyperplasia. After these situations, the patient was consulted & referred to the department of Pediatrics and Otorhinolaryngology.