Usefulness of Bolus Administration Using the FLEX Mode(Bolus Infusion Mode)for Baclofen Tolerance

: Intrathecal baclofen(ITB)is used to treat intractable spasticity of various etiologies and can provide better control of spasticity through the adjustment of the dose administered through the pump. However, in patients who develop tolerance to baclofen with the standard simple continuous mode, a sharp increase in dose becomes necessary, and spasticity can become harder to control. We investigated whether switching from the simple continuous mode to the bolus infusion mode was effective in controlling spasticity in patients with baclofen tolerance. We reported four patients undergoing ITB therapy at our facility who were considered to have developed baclofen tolerance. We observed the number of bolus infusions and total dose suitable for maintaining spasticity control after switching from the simple continuous mode to the bolus infusion mode. After switching to the bolus infusion mode, the total dose could be reduced in the short term; however, in the long term, the frequency of bolus infusions had to be increased to maintain spasticity control. Two years after changing to bolus infusion six times a day, the total dose was higher than that in the simple continuous mode for two of the four patients, and was the same level in the other two patients. Our four cases suggest that bolus infusion is effective in patients with baclofen tolerance during ITB therapy. Therefore, the conditions of bolus infusion should be further investigated.