Fentanyl | According to its data sheet: The use of fentanyl in patients who have not previously received opioids has been associated with very rare cases ofsignificant respiratory depression or mortality when used as initial opioid therapy >. There is a risk of serious or fatal hypoventilation, even when the lowest dose of fentanyl is used at the start of therapy in patients who have not previously received opioids.| Fentanyl can cause bradycardia | There is a possibility of developing serotonin syndrome, which can be fatal, if active serotonergic principles are used at the same time
4.4. Warnings and special precautions for use
Status of people who have not received opioids before and those who do not tolerate them
The use of fentanyl in patients who have not previously received opioids has been associated with very rare cases of significant respiratory depression or mortality when used as initial opioid therapy, especially in patients with pain without cancer. There is a risk of severe or fatal hypoventilation, even if the lowest dose of fentanyl is used at the beginning of therapy in patients who have not received prior opioids, especially in older patients or patients with impaired liver or kidney function. The trend from development to tolerance varies widely among people. Fentanyl is recommended for use in patients who have demonstrated tolerance to opioids (see section 4.2).
As with all potent opioids,some patients may experience significant respiratory depression with fentanyl; Patients should be monitored for these effects. Respiratory depression may persist after patch removal.
Chronic lung disease
Fentanyl may have more serious side effects in patients with chronic obstructive pulmonary disease or other lung diseases.
Fentanyl can cause bradycardia and should therefore be administered with caution to patients with bradyarrhythmias.
Opioids can cause hypotension, especially in patients with acute hypovolemia.
There is a possibility of developing serotonin syndrome, which can be fatal, if active serotonergic substances, such as selective inhibitors, are used at the same time serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs) and active substances that affect serotonin metabolism (including monoamine oxidase inhibitors [MAOIs]). This can occur with the recommended dose.
Serotonin syndrome may include mental status changes (eg, excitement, hallucinations, coma), autonomic instability (eg, tachycardias, high blood pressure labile blood pressure, hyperthermia), neuromuscular abnormalities (eg, hyperreflexia, incoordination, rigidity), or gastrointestinal symptoms (eg, nausea, vomiting, diarrhoea). If serotonin syndrome is suspected, fentanyl should be discontinued.