When you're having trouble getting the quality sleep your internal clock craves, add some Zzz's to your night with ZzzQuil. This non-habit-forming sleep-aid helps you get some shut-eye, so you can wake up feeling refreshed.. Do not use: For children under 12 years of age. With any other product containing diphenhydramine, even one used on skin. With other drugs that cause drowsiness such as antihistamines and nighttime cold/flu products Do not use with NyQuil®