It is not safe to drink alcohol while taking DayQuil. Drinking alcohol with DayQuil can cause serious side effects including liver damage or failure due to the combination of acetaminophen and alcohol being toxic for the liver. It can also increase drowsiness, dizziness, nausea, impaired coordination, increased heart rate and blood pressure, stomach bleeding, and risk of unconsciousness. These effects are intensified by alcohol's depressant impact combined with DayQuil's active ingredients like dextromethorphan and phenylephrine. It is generally recommended to avoid alcohol consumption while taking DayQuil, and if alcohol is consumed, one should wait at least 4 to 6 hours after taking DayQuil before drinking alcohol, though the safest course is to avoid mixing them altogether.
