Interaction between Fentanyl and Selegiline
Major
Others
| ID | DDInter722 and DDInter1653 |
| Interaction | Coadministration of monoamine oxidase inhibitors (MAOIs) with certain opioids has been associated with rare reports of severe and fatal adverse reactions. There appear to be two types of interaction, an excitatory and a depressive one. Symptoms of the excitatory reaction may include agitation, headache, diaphoresis, hyperpyrexia, flushing, shivering, myoclonus, rigidity, tremor, diarrhea, hypertension, tachycardia, seizures, and coma. The exact mechanism of interaction is unknown, but may involve excessive serotonergic activity in the central nervous system (i.e., serotonin syndrome). The interaction is unpredictable and has been reported primarily with meperidine or fentanyl and various MAOIs including phenelzine, tranylcypromine, linezolid, moclobemide, and selegiline. Fatal hyperpyrexia and hypertension have also been observed in animal studies with meperidine and phenelzine or furazolidone. In contrast, symptoms of the depressive reaction probably stem from potentiation of CNS effects by MAOIs and include respiratory depression, cyanosis, hypotension, and coma. |
| Management | Meperidine and fentanyl should not be used with MAOIs or other agents that possess MAOI activity (e.g., furazolidone, linezolid, methylene blue, procarbazine). Some manufacturers of MAOIs also contraindicate the concomitant use of propoxyphene and methadone due to their possible serotonergic effects. At least 14 days should elapse between discontinuation of MAOI therapy and initiation of treatment with these opioids. Although morphine may also have significant CNS interactions with MAOIs, it is generally considered a safer alternative in patients treated with MAOIs who require a narcotic analgesic. |
| References | |
| Alternative for Fentanyl |
N01A
N02A |
| Alternative for Selegiline |
N04B
|
Potential Metabolism Interactions
Substrate-Substrate Interaction：If more than one drug is metabolized by the same CYP, it is possible that its metabolism is inhibited because of the competition between the drugs. That means, it can be useful to lower the dosage of the drugs in the drug-cocktail because they remain longer in the organism than in monotherapy.
Inhibitor-Inhibitor Interaction：Combining two or more inhibitors of one CYP, should be compensated by lowering the dosage of these drugs because the metabolism is reduced and the drugs remain longer in the organism than in monotherapy. Not adapting the dosage bears the risk of even more side effects.
Inhibitor-Substrate Interaction：Combining drugs that have inhibitory effect and are substrates of one particular CYP, should be compensated by lowering the dosage. They rest longer in the organism than in monotherapy. Not adapting the dosage bears the risk of even more side effects.