What is a potential adverse effect to monitor for in neonates after magnesium sulfate administration?

Monitoring for lethargy and respiratory depression in neonates after magnesium sulfate administration is crucial due to the effects of magnesium on the central nervous system and respiratory function. Magnesium sulfate is often used in obstetric settings for conditions like pre-eclampsia or to prevent preterm labor; however, it can lead to a range of adverse effects, particularly in neonates if the mother received it during pregnancy.

Magnesium acts as a muscle relaxant and can depress the nervous system. In neonates, this may manifest as lethargy, decreased muscle tone, and even respiratory depression. The decreased respiratory effort can lead to insufficient oxygenation and the need for immediate medical intervention. Therefore, it is vital for healthcare providers to closely monitor any signs of these complications in newborns who were exposed to magnesium sulfate in utero.

In contrast, the other options like hyperactivity, increased appetite, or constipation do not typically correlate with magnesium sulfate use in neonates, as magnesium's primary effects are more about sedation and respiratory response rather than stimulating activity or appetite. Thus, the potential for lethargy and respiratory depression directly aligns with the pharmacological effects of magnesium sulfate.