What is the SIG for intranasal naloxone 2 mg/2 mL prefilled syringe?

The SIG for intranasal naloxone 2 mg/2 mL prefilled syringe is to spray 1/2 into each nostril. This administration method is designed for effective delivery of naloxone, an opioid antagonist used to reverse opioid overdoses. When naloxone is given intranasally, it allows for rapid absorption across the nasal mucosa, providing a quick onset of action which is critical in overdose situations.

Using half of the total dose in each nostril maximizes the exposure of the drug to the nasal membranes and ensures optimal effectiveness. This method also allows for easier delivery than some other routes, which may require more equipment or training (e.g., injections).

In the context of the other options, administering a spray into the mouth or swallowing the contents does not utilize the formulation's intended route of administration and would significantly reduce its efficacy. Similarly, injecting the solution subcutaneously misapplies the drug and ignores the established practice for nasal formulations. Therefore, using half in each nostril is the correct method to use intranasal naloxone effectively in emergencies.