Hyperinsulinemic hypoglycemia (HH) includes a diverse group of disorders characterized by dysregulated insulin secretion, exhibiting clinical, genetic, and morphological heterogeneity. It is associated with permanent brain damage. Hence, a timely diagnosis and prompt management are essential to safeguard against complications such as epilepsy, cerebral palsy, and neurodevelopmental deficits. We report the challenges faced in the management of HH in a preterm neonate. A baby girl was born to a G2A1 mother at 31 weeks of gestation due to preterm onset of labor with premature rupture of membranes. The baby had persistent and refractory hypoglycemia requiring oral and parenteral medications such as diazoxide, hydrochlorothiazide, hydrocortisone, nifedipine, glucagon infusion, and subcutaneous octreotide. Genetic testing unveiled a homozygous pathogenic mutation of the ABCC8 gene with autosomal recessive (AR) inheritance. As the AR inheritance always presents with diffuse lesions, a 18F-fluoro-dihydroxyphenylalanine positron emission computed tomography (18F-DOPA PET) scan was not done to differentiate focal and diffuse lesions. The baby underwent laparoscopic near-total pancreatectomy and was discharged on subcutaneous octreotide. Continuous intravenous glucagon infusion may help reduce the infusion rate of glucose needed to maintain normoglycemia. Diazoxide unresponsiveness in a baby with HH needs genetic studies. AR inheritance always presents as diffuse lesions. Hence, an 18F-DOPA PET scan can be deferred to differentiate the diffuse and focal forms.