Institutional approval and written informed consent from parents or guardians of healthy children, with obstructive sleep apnea (OSA) and/or with increased end-tidal C02 (sleep related hypoventilation, obstructive hypoventilation or sustained alveolar hypoventilation), confirmed with sleep study, scheduled for elective outpatient or inpatient adeno-tonsillectomy at our hospital, will be obtained. The study will be prospective, randomized, double blinded and placebo controlled. A computer generated randomization list will be used, and the study will be registered with clinical.trials.gov. Written child assent will be obtained from children 7 years and older. Copies of a flyer and an explanation of the study will be provided at the office of all the pediatric ENT surgeons who practice at the Memorial Hermann Hospital OR. The investigators will communicate with the nurses at the surgeons' office and ask them to give the flyer with an explanation of the study to the parents and children on the day they schedule the surgery. The flyer with an explanation of study will be sent to IRB for review and approval. A research assistant will invite parents or guardians in the DSU unit, anesthesia clinic or on the floor to allow their children to be part of the study. Children with OSA and/or increased end tidal C02 (sleep related hypoventilation, obstructive hypoventilation or sustained alveolar hypoventilation), 2-12 years of age, and both genders will be eligible to be part of the study. OSA and its severity will be diagnosed by a preoperative polysomnography. Children with compromised cardiovascular, pulmonary or renal function, those with congenital syndromes, sickle cell disease, history of seizures and those receiving theophylline will be excluded.