Final answer:
The nurse should administer Naloxone, an opioid antagonist, to reverse opioid-induced respiratory depression caused by morphine. Other drugs like Lorazepam, Acetaminophen, or Furosemide are not appropriate in this situation.
Step-by-step explanation:
A nurse assessing a client who is experiencing a significantly reduced respiratory rate of eight per minute, following the administration of morphine for pain after a cesarean birth, should be concerned about opioid-induced respiratory depression. Morphine is a potent opioid analgesic often used for severe pain, but it can lead to life-threatening respiratory depression. In this case, the appropriate medication to administer would be Naloxone. Naloxone is an opioid antagonist that can quickly reverse the effects of opioid overdose, including the restoration of normal respiratory function.
Neither Lorazepam, which is a benzodiazepine and can exacerbate respiratory depression, nor Acetaminophen, a non-opioid pain reliever, nor Furosemide, a diuretic, are appropriate medications in this situation. Only Naloxone is indicated because of its ability to antagonize morphine at the receptor level, reversing the potentially fatal respiratory depression.