Use of Terbutaline or a Reduction in Basal Insulin in the Prevention of Nocturnal Hypoglycemia

Inclusion Criteria: * Clinical diagnosis of Type 1 Diabetes and using daily insulin therapy for at least one year. * Age 10 to 17 years, inclusive. * HbA1c \< 10.0%. * BMI 5-95th % for age and gender. * Stable Continuous Subcutaneous Insulin Infusion regimen for at least 1 month and not anticipating a change prior to the subject's completion of the study. * Subject uses a downloadable insulin pump. * Normal thyroid function (measured within the previous year). * For females, subject not intending to become pregnant during the study. * No expectation that subject will be moving out of the area for the duration of the study. * Informed consent form signed and understood by the parent/guardian and Child Assent form signed/understood by subjects. Exclusion Criteria: * The presence of a significant medical disorder (including epilepsy, or any cause of seizures other than hypoglycemia) that in the judgment of the investigator will affect the wearing of the sensors or the completion of any aspect of the protocol. * A recent injury to body or limb, Addison's disease, muscular disorder or disease in the judgment of the investigator that will affect the completion of the exercise protocol. * Asthma which has been medically treated within the last year. * Medically diagnosed cardiac disease, hypertension, or autonomic dysfunction. * Use of pseudoephedrine 48 hours prior to the visit (if used in the 48 hours prior to the scheduled visit, the visit will be deferred) * Severe hypoglycemia resulting in seizure of loss of consciousness in the 3 months prior to a visit. * Active infection (if at the time of the scheduled visit and infection is present, the visit will be deferred). * Anticipating a significant change in exercise regimen between visits (i.e. starting or stopping an organized sport). * Treatment with systemic or inhaled corticosteroids in the last 6 months. * Current treatment with B-blockers or presenting with high blood pressure. * Inpatient psychiatric treatment in the past 6 months for either the subject or the subject's primary care giver. * Current use of oral/inhaled glucocorticoids or other medications, which in the judgment of the investigator would be a contraindication to participation in the study * Known allergy to Terbutaline * Treatment with atenolol (Tenormin), carteolol (Cartrol), labetalol (Normodyne, Trandate), metoprolol (Lopressor), nadolol (Corgard), phenelzine (Nardil), propranolol (Inderal), sotalol (Betapace), theophylline (Theo-Dur), timolol (Blocadren), tranylcypromine (Parnate), other medications for asthma, heart disease or depression. * Treatment with ephedrine, phenylephrine, phenylpropanolamine, or pseudoephedrine. * The presence of an irregular heart beat, increased heart rate glaucoma or an overactive thyroid gland.