Central Potassium Channel Blockers

Potassium channel blockers are not currently used in bowel care management, but two randomized controlled trials demonstrate its potential benefits for bowel after SCI (Cardenas et al. 2007; Cardenas et al. 2014). 4-aminopyridine (fampridine) may improve excitability in damaged nerves but this mechanism requires further study.

Discussion

A study by Cardenas et al. (2007) examined fampridine dosages of 25 mg and 40 mg compared to placebo and reported higher efficacy and tolerability with the lower dosage for people with incomplete SCI. They also reported an increase in the number of days with bowel movements in approximately one-fifth of the participants given sustained-release fampridine (selective potassium channel blocker). Based on these findings, another trial investigated the use of a 25 mg dosage twice a week in two identical RCTs (SCI-F301 in the US and SCI-F302 in Canada) (Cardenas et al. 2014). Though, bowel was a secondary outcome in this study, findings showed an increased number of bowel movements per day only in one RCT (SCI-F302; p=0.006).

Conclusion

There is level 1 evidence from one RCT (Cardenas et al. 2007) that fampridine can increase the number of days with bowel movements in people with incomplete SCI.

There is level 2 evidence from one RCT (Cardenas et al. 2014) that fampridine can increase the number of bowel movements per day in people with incomplete SCI.