Vicks NyQuil Nighttime Relief contains dextromethorphan hydrobromide, acetaminophen and doxylamine, notes WebMD. It is an over-the-counter medication used to treat breathing problems and other symptoms caused by the common cold, flu or allergies.
Each ingredient in NyQuil Nighttime Relief has a specific symptom it treats, and they work together to cover a wide range of cold and flu symptoms. Dextromethorphan hydrobromide, or DM, is a cough suppressant that works by reducing the urge to cough, explains WebMD. Acetaminophen is a pain reliever that does not belong to the same class of drugs as aspirin. Unlike ibuprofen and other nonsteroidal anti-inflammatory drugs, acetaminophen reduces fever but does little for inflammation. The last ingredient is the antihistamine doxylamine, which treats watery and itchy eyes, sneezing, and runny nose.
These medications treat the symptoms of common colds and the flu, but they do not cure them or shorten their duration, states WebMD. They have not been shown to be effective or safe in treating these symptoms in children under 6. NyQuil Nighttime Relief specifically should only be given to those over the age of 12. Each ingredient also has a number of drug interactions and side effects, and the drug should only be taken after consulting with a doctor or pharmacist.