Zopiclone may produce additive CNS depressants effect when co-administered with alcohol, sedative antihistamines, anticonvulsants or psychotropic medications which themselves can produce CNS depression.
Compounds which inhibit certain hepatic enzymes (particularly cytochrome P450) may enhance the activity of benzodiazepines and benzodiazepine-like agents. Examples include cimetidine or erythromycin.