The effects of donepezil
are expected to oppose the actions of drugs with antimuscarinic effects, and in turn to be opposed by antimuscarinics
. However, in practice two cases describe confusional states resulting from the concurrent use of anticholinesterases and drugs with antimuscarinic effects, which is the opposite effect to that expected.
Whether this interaction is of real practical importance awaits confirmation. Monitor concurrent use for an increase in adverse effects.