If you are only using NyQuil Cold and Flu Nighttime Relief Liquid, it can be taken every 6 hours, but do not exceed 4 doses within 24 hours. If you have taken 4 doses of NyQuil in one day, do not take DayQuil in the same day unless recommended by your healthcare provider. The do...
DayQuil Cough can be taken every 6-8 hours. Q: How long does DayQuil last? A: DayQuil treats cold and flu symptoms for approximately four hours. DayQuil Cough provides up to 8 hours of cough relief. Q: How long does it take for DayQuil to work? A: This depends on many factors but ...