Gabapentin therapy for pain and irritability in a neurologically impaired infant

Abstract

Gabapentin is a gamma-aminobutyric acid analog used for numerous neurologic conditions, including neuropathic pain and epilepsy. We describe a 39-week gestational age, male infant with hypotonicity, functional short gut, and microduplication of chromosome 22 who was treated with gabapentin to control pain and irritability. During his hospitalization, the infant experienced multiple complications including respiratory distress, persistent pulmonary hypertension of the newborn, hypocalcemia, hypoglycemia, hyperbilirubinemia, gastroesophageal reflux, necrotizing enterocolitis, and cholestatic jaundice. Pain associated with related invasive procedures and surgeries was treated with intermittent and scheduled morphine. In addition to postoperative and procedural pain, the infant continued to experience pain and irritability attributed to neurologic impairment, presumably secondary to his chromosomal abnormality. Trials of scheduled lorazepam along with intermittent morphine and phenobarbital were unsuccessful in managing these symptoms. After failure of nonpharmacologic treatment and continued trials of sedatives and analgesics, gabapentin 5 mg/kg at bedtime was started on day of life 98. Improvement in the infant's tone and disposition was noted by numerous health care professionals and the infant's mother. In addition, the infant's pain scores, using the Pain Assessment in Neonates Scale, showed marked improvement. The infant continued to receive gabapentin; the dosage was increased to 10 mg/kg at bedtime after 6 days, then to 5 mg/kg in the morning and 10 mg/kg at bedtime 10 days later. When the infant was 7 months old, his mother requested that gabapentin be discontinued. He was slowly weaned, and the drug was discontinued when he was 11 months old. The infant tolerated gabapentin well except for experiencing nystagmus, which was noted 31 days after starting the drug and resolved after drug discontinuation. Clinicians should be aware of gabapentin as an alternative treatment for pain and irritability in neurologically impaired infants. Further study is needed, however, to verify the drug's safety and efficacy in neonates and infants. Standardized pain scales along with close patient monitoring will help to guide clinicians in dosage titration to optimize therapy.