What action should a nurse take if an infant's serum digoxin level is 0.6 ng/mL?

The appropriate action for a nurse to take when an infant's serum digoxin level is 0.6 ng/mL is to administer the prescribed dose. The therapeutic range for digoxin levels in children typically falls between 0.5 to 2.0 ng/mL, with 0.6 ng/mL being within this range. This indicates that the drug concentration is adequate for therapeutic effect and does not pose a risk of toxicity.

It is crucial to interpret digoxin levels in conjunction with the infant's clinical status and any symptoms they may be exhibiting. If the infant shows no signs of digoxin toxicity, such as bradycardia, vomiting, or any distress, then administering the prescribed dose is warranted.

Other actions, such as withholding the dose and notifying the healthcare provider, or obtaining a repeat blood sample, would be appropriate if the digoxin level were outside the expected therapeutic range or if the infant exhibited signs of toxicity. Administering a higher dose would only be indicated if there were significant clinical reasons to increase the dosage, which is not the case here given the current level within the therapeutic window.