Intravenous infusion of 4-AP in chronic spinal cord injured subjects

Study design: A prospective double blind cross over trial of intravenous 4- Aminopyridine (4AP). Objective: To determine the efficacy of this drug in the treatment of spina l cord injured (SCI) patients for neurologic impairment, pain and spasticit y. Setting: The post anesthesia care unit (PACU) of a tertiary care acute hosp ital. Methods: Twelve paraplegic patients were enrolled in a double blind cross o ver intravenous trial of 4-Aminopyridine (4-AP). Thirty milligrams of 4-AP or placebo were administered over a 2 h period. Patients were serially exam ined during and after the infusion clinically for pain, sensorimotor functi on, hypertonicity and motor control using electromyography (EMG). Samples o f blood and cerebrospinal fluid (CSF) were also analyzed at similar interva ls. Results: Despite penetration of 4-AP into the CSF, no significant differenc es were noted in the clinical and EMG parameters at the times measured. Ind ividual changes in sensory function were reported by some patients in both the placebo and 4-AP trials, however mean values were not robust. Frequentl y, patients complained of -unpleasant symptoms during the 4AP infusion. Conclusion: The intravenous route may not, be the best way to administer th is drug as no short term benefits were observed.