Respiratory system opioids affecting

Increased doses of opioid analgesics also expose the patient to adverse side effects such as respiratory depression. Opioid analgesics can cause some respiratory depression. However, this effect usually does not occur with longterm use such as with cancer patients. Prescribers avoid this side effect by titrating doses over time to deliver pain relief without adversely affecting the respiratory system. 

Fentanyl, sufentanil, and alfentanil are frequently used before anesthesia and surgery as a sedative and analgesic, as well as a continuous infusion for primary anesthesia. Because opioids rarely affect the cardiovascular system, they are particularly useful for cardiac surgery and other high-risk cases. Opioids act directly on spinal cord receptors, and are frequently used in epidurals for spinal anesthesia. Side effects may include nausea and vomiting, itching, and respiratory depression. 

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