Cimetidine moderately raises hydroxyzine levels and considerably raises loratadine
levels, but this is not thought to be of clinical
significance. The manufacturer of mizolastine recommends caution if cimetidine
is taken concurrently because it might increase mizolastine levels and prolong the QT interval. This is a cautious approach since a link between mizolastine and cardiac arrhythmias has not been proven.
No action needed.