How long should clortrimazole take to work on oral thrush?

A few days to a week: A few days to a week.

No more nystatin nee: It can take anywhere from 4 to 10 days to clear oral thrush.

Works quickly: You should start seeing improvement in a few days but keep taking the medication for as long as it was prescribed or it may recur.

THrush: Thrush is not a common illness in an otherwise healthy adult. Please see your primary care doctor to review cause and care.