Hello! I m wondering if it is okay to take one adult dosage of Nyquil (30ml) after already taking three adult doses of Dayquil? I ve been dealing with a cold the past two days, and it really started to to get worse the second day (today). I have been dealing with nasal congestion, phlegm, coughing, fever, and a headache (your typical cold symptoms). Can I take one dose of Nyquil? Or is there a possibly of overdose if I take it? I am a white, 21 year old male that is 6 foot 2 inches and around 195lbs. I don t know if that info helps but I thought I would add that in there anyways.