For a client receiving magnesium sulfate for gestational hypertension, which medication should the nurse have on hand for potential toxicity?

When administering magnesium sulfate for gestational hypertension, it is crucial for the nurse to be aware of the potential for magnesium toxicity. Magnesium sulfate can lead to adverse effects such as respiratory depression, hyporeflexia, and cardiac arrest if blood levels become too high. Calcium gluconate is the appropriate antidote for magnesium toxicity. It works by providing a source of calcium that can counteract the effects of magnesium on the neuromuscular and cardiac systems, thereby reversing the toxic effects.

The presence of calcium gluconate allows the healthcare provider to respond promptly in the event of signs of toxicity, ensuring the patient's safety is prioritized. In cases of severe toxicity, administering calcium gluconate can help stabilize the patient until magnesium sulfate can be safely discontinued and the magnesium levels are normalized.

The other medications listed do not serve as an antidote for magnesium toxicity. Oxytocin is typically used to manage labor and delivery and does not address magnesium-related issues. Terbutaline is a bronchodilator used primarily for asthma or to halt preterm labor but does not have a role in managing magnesium toxicity. Naloxone is an opioid antagonist and is specific for reversing opioid overdose but is not effective in treating complications that arise from magnesium sulfate administration.