Is it safe for a 9 year old to take a 1/2 a dose of Nyquil?
Yes, it is perfectly fine as long as the child has no allergies, and only once a night.
Personally I would not give it to children. Drugs to children are usually administered based on their weight. If the packaging does not specifically indicate how much to give child it is because it is not recommended for children. Better to check with child's pediatrician or a pharmacist.
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