What is the first medication to administer if you suspect narcotic overdose in a patient on a Morphine PCA?

Naloxone, commonly known by its brand name Narcan, is the first medication to administer in the case of a suspected narcotic overdose, especially in a patient on a Morphine PCA (Patient-Controlled Analgesia). This is because naloxone is an opioid antagonist that works by competitively binding to opioid receptors in the central nervous system. It effectively reverses the effects of opioid medications, including respiratory depression, sedation, and hypotension, which are key symptoms of an opioid overdose.

In situations where a patient has potentially taken too much morphine, naloxone can rapidly restore normal respiratory function and consciousness. The prompt administration of naloxone can be life-saving, making it the most appropriate initial treatment in this scenario.

The other medications listed serve different purposes. Ativan, an anti-anxiety medication, does not address the respiratory depression caused by opioid overdose. Fentanyl is also an opioid and would exacerbate the overdose situation. Adrenaline (epinephrine) is a vasopressor used primarily in cases of severe allergic reactions or cardiac arrest, and it is not indicated for opioid overdose. Thus, naloxone is the clear choice when managing potential narcotic overdose.