Is it possible to use GABA supplement or passion flower when tapering off benzodiazepines? Ashton manual is very popular for people tapering off benzodiazepines, and in that manual they don't recommend using GABA or herbs like valerian and passion flower while tapering off benzodiazepines. And they also claim that GABA supplements don't cross blood brain barrier.....is this true? May i ask your opinion for these?