NyQuil
brand of medication
Vicks NyQuil is a brand of over-the-counter medication manufactured by Procter & Gamble intended for the relief of various symptoms of the common cold. All medications within the NyQuil imprint contain sedating antihistamines; they are intended to be taken before sleep. Its daytime counterpart is antihistamine-free DayQuil, formulated to avoid drowsiness. NyQuil is also used as a sleep aid. NyQuil was first marketed in the United States in 1966.
Products
NyQuil Cold/Flu Multisymptom Relief
The liquid version of NyQuil Cold/Flu Multi-symptom Relief, available in syrup and LiquidCap form. The recommended adult dose contains:
Acetaminophen (650 mg/30 mL) (pain reliever/fever reducer)
Dextromethorphan (30 mg/30 mL) (cough suppressant)
Doxylamine succinate (12.5 mg/30 mL) (antihistamine/hypnotic)
The LiquiCap capsule version has the following active ingredients per pill, half the recommended adult dose:
Acetaminophen (325 mg/pill) (pain reliever/fever reducer)
Dextromethorphan (15 mg/pill) (cough suppressant)
Doxylamine succinate (6.25 mg/pill) (antihistamine/hypnotic)
The liquid version of NyQuil SEVERE Cold/Flu Multi-symptom Relief, available in syrup and LiquidCap form. The recommended adult dose contains:
Acetaminophen (650 mg/30 mL) (pain reliever/fever reducer)
Dextromethorphan (20 mg/30 mL) (cough suppressant)
Doxylamine succinate (12.5 mg/30 mL) (antihistamine/hypnotic)
Phenylephrine (10 mg/30 mL) (nasal decongestant)
The LiquiCap capsule version has the following active ingredients per pill, half the recommended adult dose:
Acetaminophen (325 mg/pill) (pain reliever/fever reducer)
Dextromethorphan (15 mg/pill) (cough suppressant)
Doxylamine succinate (6.25 mg/pill) (antihistamine/hypnotic)
Phenylephrine (5 mg/pill) (nasal decongestant)
NyQuil D
NyQuil D contains pseudoephedrine, a decongestant that in some regions (such as the United States) is now placed behind the counters at pharmacy and other retail stores and must be requested by the customer. It contains the following active ingredients (15 mL is one tablespoon, half the recommended adult dose):
Acetaminophen (500 mg/15 mL) (pain reliever/fever reducer)
Dextromethorphan (15 mg/15 mL) (cough suppressant)
Doxylamine succinate (6.25 mg/15 mL) (antihistamine/hypnotic)
Pseudoephedrine (30 mg/15 mL) (nasal decongestant)
NyQuil Cough
Nyquil Cough contains a cough suppressant and antihistamine but no painkiller. Its active ingredients are:
Dextromethorphan (15 mg/15 mL) (cough suppressant)
Doxylamine succinate (6.25 mg/15 mL) (antihistamine/hypnotic)
NyQuil Sinus
Nyquil Sinus's active ingredients are:
Acetaminophen (pain reliever/fever reducer)
Doxylamine succinate (antihistamine/hypnotic)
Phenylephrine (nasal decongestant)
Nyquil Sinus is available as LiquiCaps only.
This brief starts where responsible research should: with the source description of “NyQuil” as brand of medication. Everything that follows is an evidence route, not borrowed authority.
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The subject matters to the general reference register because the source frames it as brand of medication. Its deeper value depends on whether names, dates, institutions and citations support that framing.
Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Aug 11, 2026. The linked authority identifier is Q7070750. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1966.
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This entry incorporates text from “NyQuil” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.