The objective of this demonstration project is to compare a novel long-acting starch, Glycosade, a hydrothermally processed high amylopectin maize starch, versus gastrostomy tube-dextrose infusion in maintaining euglycaemia overnight in children with GSD-I. Glycosade has been reported to increase the duration of euglycaemia. Its slow release and longer periods of normal blood sugar achieved would preclude the need for the overnight dextrose infusion and eliminate the need for the surgical insertion of a gastrostomy tube for this purpose. Glycosade also reportedly causes fewer gastrointestinal side effects, thus potentially improving compliance to therapy. The investigators intend to evaluate Glycosade in our patients and determine its efficacy on glucose control, on the length of normoglycemia achieved and to determine if there are reduced side effects in our patients with GSD-I. This will be accomplished by an open label study of Glycosade in GSD-I patients who consent to the protocol.

Inclusion Criteria:

• Diagnosis of GSD Type 1
• Age >5 years

Exclusion Criteria:

• n/a