DayQuil & NyQuil Medicine For Severe Cold Flu And Congestion VapoCOOL. Cooling Relief. Day & Night Pack. Dayquil for Headache, Fever, Sore Throat, Minor Aches & Pains, Chest Congestion, Thinning & Loosening Mucus, Nasal Congestion, Sinus Pressure, and Cough. Nyquil for Headache, Fever, Sore Throat, Minor Aches & Pains, Nasal Congestion, Sinus Pressure, and Cough.