Neonatal Abstinence Syndrome: Update on Diagnostic and Therapeutic Strategies

Abstract

Substance use among pregnant women is a major public health issue. Both prescription opioid use and illicit opioid abuse have increased dramatically in recent years. Prolonged in utero drug exposure may result in neonatal abstinence syndrome (NAS), an acute multisystemic clinical entity that occurs in the first days of life. This syndrome is caused by abrupt discontinuation of fetal exposure to licit or illicit drugs chronically consumed by the mother during pregnancy and transmitted to the fetus through the placenta. It usually requires prolonged hospitalization and may have long-term effects. The interplay of many factors contributes to its clinical heterogeneity, and its pathophysiology has not been fully unveiled. The first step in NAS management consists of nonpharmacologic interventions and includes promoting breastfeeding when not contraindicated. If withdrawal signs become severe, pharmacotherapy is needed. The Finnegan scoring system supports care providers across the pharmacotherapy process from initiation through the monitoring phase, until weaning and discontinuation. However, a standardized approach to pharmacotherapy is still lacking. Morphine is usually the first-line agent to treat NAS. Methadone is a valid option, but its safety profile is not completely known. Phenobarbital, despite its lack of effect on gastrointestinal symptoms and unfavorable pharmacologic features, has been identified as a second-line agent to be used in infants unresponsive to opiates. Although buprenorphine and clonidine seem promising, their use requires further validation. Long-term developmental effects of NAS therapy call for more-comprehensive, longitudinal assessments. In this article, key points for use of recommended therapies are outlined, and directions for future research are suggested.

Genomics and Neonatal Opioid Withdrawal Syndrome

“…It is difficult to accurately predict which infants will respond best to nonpharmacological measures versus infants necessitating pharmacological treatment. The therapeutic developmental and placental pharmacology implications tend to amplify the pathogenetic mechanisms of NOWS (Raffaeli et al, 2017). Opioids readily pass through the fetoplacental barrier, blood-brain barrier, and breast milk due to the lipophilic properties of the drugs.…”

“…Opioids readily pass through the fetoplacental barrier, blood-brain barrier, and breast milk due to the lipophilic properties of the drugs. The passage of the drugs increases as the placenta matures and the pregnancy advances, hence, NOWS emerges at a higher rate in term neonates than in preterm neonates (Raffaeli et al, 2017). The analgesic effect of maternal opioids acts upon the neonate opioid receptors expressed in the central nervous system (CNS), autonomic nervous system (ANS), and enteric nervous system (Cole et al, 2017).…”

“…Post-delivery, the chronic stimulation of the opioid receptors induced by maternal drugs, ceases. Subsequently, the neonate experiences an increase in excitatory neurotransmitters (norepinephrine, acetylcholine, corticotropin) with a corresponding decrease in inhibitory neurotransmitters (serotonin and dopamine) (Raffaeli et al, 2017). The resultant heterogeneous elements of neurotransmitter imbalance may serve as a contributing factor related to the variable expression of NOWS withdrawal symptoms and consequent severity (Cole et al, 2017).…”

Opioid Use and Abuse and Neonatal Abstinence Syndrome

“…need. Raffaeli et al 11 review diagnostic and therapeutic strategies with a European perspective. Tran et al 12 provide a therapeutic review of accepted approaches for the treatment of opioid use in pregnant women.…”

“…Two perspectives address this need. Raffaeli et al . review diagnostic and therapeutic strategies with a European perspective.…”