Neurotoxicity is a result of excessive CNS excitation:
(1) seizures
(2) agitation, nervousness or irritability
(3) tremors
(4) myoclonus
Groups at increased risk for experiencing normeperidine neurotoxicity:
(1) renal failure or impaired renal function
(2) repeated use of high meperidine doses for a prolonged period
(3) elderly adults >= 65 years of age
(4) sickle cell disease
(5) cancer patients
(6) history of seizure disorder
(7) concurrent therapy with a drug that lowers the seizure threshhold
The diagnosis can be documented by demonstrating an elevated plasma level of normeperidine.
Differential diagnosis:
(1) serotonin syndrome (may be triggered by meperidine)
Management:
(1) Discontinuation of meperidine therapy may be sufficient if the neurotoxicity is mild.
(2) Hemodialysis has been effective in severe intoxications.
(3) Naloxone is ineffective.
