What is the correct icd-9 code for hypermagnesemia in a newborn?

ICD-9-CM designates diagnosis code 775.5 for Neonatal Hypermagnesemia. This code is found in the Index to Disease under Hypermagnesemia, see subterm neonatal 775.5. ICD-9-CM Chapter 3 Endocrine codes are excluded from assignment on a newborn's chart, when there is a specific code designated elsewhere in ICD-9-CM. This condition, Neonatal Hypermagnesemia does not require assignment of an additional code from Chapter 3. The Chapter 15 Neonatal code 775.5 is the designated code assignment.