Head-to-head comparisons of medication uses, side effects, warnings, and more.
Key takeaways
Doxylamine (Unisom SleepTabs) and Nyquil Cold and Flu are both over-the-counter medications, but they have several differences. Doxylamine is a single-ingredient antihistamine used primarily as a sleep aid to help you fall asleep by blocking histamine in the brain. In contrast, Nyquil Cold and Flu is a combination medication that includes acetaminophen (a pain reliever), dextromethorphan (a cough suppressant), and doxylamine (an antihistamine). Nyquil is used to relieve multiple cold and flu symptoms like cough, sore throat, and fever. While both medications contain doxylamine, Nyquil also addresses pain and cough, making it more versatile for cold and flu symptoms. Doxylamine is typically taken once nightly, whereas Nyquil Cold and Flu can be taken every 6 hours as needed. Both can cause sleepiness, but Nyquil's additional ingredients mean you need to be cautious about potential liver damage from acetaminophen and interactions with other medications.
Doxylamine succinate (Unisom SleepTabs) is an over-the-counter antihistamine that can be taken by adults and children ages 12 years and older who are having trouble falling asleep. It's a sleep aid that works by blocking certain chemicals (histamine) in your body. Doxylamine (Unisom SleepTabs) is taken by mouth once a day, about 30 minutes before bedtime. The most common side effect of this medication is next-day sleepiness.
Summary for Analgesic / Cough suppressant / Antihistamine
Nyquil Cold and Flu is a combination medication containing acetaminophen (a pain reliever), dextromethorphan (a cough suppressant), and doxylamine (an antihistamine). It's used to treat cold and flu symptoms, like sore throat, fever, cough, runny nose, sneezing, and aches, in adults and children. Nyquil Cold and Flu is available as pills and a liquid. This medication can make you feel sleepy and dizzy as side effects.