Respiratory Depression
Back to Misconceptions About Opioids
Correct! This is a myth. Opioids rarely cause clinically significant respiratory depression.
Therapeutic doses of morphine depress all phases of respiration, respiratory rate, and minute volume. At the same time, the responsiveness to carbon dioxide (CO2) is decreased and thus the CO2 response curve is shifted upward and to the right; however, clinically significant respiratory depression is extremely rare.
With careful titration, opioids are safe analgesics, even for patients with respiratory disease. When the patient's level of consciousness and respirations drop concomitantly, significant respiratory depression should be considered. As long as the patient is arousable, oxygenating adequately, and is breathing at a rate of more than six respirations per minute, use of an opioid antagonist (e.g., naloxone) is usually unnecessary and can be very distressing, leading to an acute abstinence syndrome and extreme pain due to reversal of analgesia.