NyQuil interactions
Overview
NyQuil (Vicks NyQuil) is a nighttime cold medicine with acetaminophen, dextromethorphan and doxylamine. In our database it has 55 known interactions with common medicines and substances: 10 serious, 39 that need caution and 6 minor.
Avoid / serious 10 interactions
Double acetaminophen can damage your liverBuprenorphine-naloxone
Too much sedation and slowed breathingCodeine
Too much sedation and slowed breathingDayQuil
Double acetaminophen can damage your liverExcedrin
Double acetaminophen can damage your liverHydrocodone
Too much sedation and slowed breathingKratom
Too much sedation and slowed breathingMorphine
Too much sedation and slowed breathingOxycodone
Too much sedation and slowed breathingTramadol
Too much sedation and slowed breathing
Use caution 39 interactions
Alcohol adds to drowsiness and dizzinessAlprazolam
Extra drowsiness and slowed reactionsAmitriptyline
Combined drowsinessAmphetamine salts
Serotonin syndrome riskBaclofen
Combined drowsinessBuspirone
Serotonin syndrome riskCannabis
Combined drowsinessCitalopram
Serotonin syndrome riskClonazepam
Extra drowsiness and slowed reactionsClonidine
Combined drowsinessCyclobenzaprine
Combined drowsinessDextromethorphan
Serotonin syndrome riskDiazepam
Extra drowsiness and slowed reactionsDiphenhydramine
Two drowsy antihistaminesDoxylamine
Two drowsy antihistaminesDuloxetine
Serotonin syndrome riskEscitalopram
Serotonin syndrome riskFluoxetine
Serotonin syndrome riskGabapentin
Combined drowsinessHydroxyzine
Two drowsy antihistaminesLevetiracetam
Combined drowsinessLisdexamfetamine
Serotonin syndrome riskLithium
Serotonin syndrome riskLorazepam
Extra drowsiness and slowed reactionsMeclizine
Two drowsy antihistaminesMethocarbamol
Combined drowsinessMirtazapine
Combined drowsinessOndansetron
Serotonin syndrome riskParoxetine
Serotonin syndrome riskPregabalin
Combined drowsinessPromethazine
Two drowsy antihistaminesQuetiapine
Combined drowsinessSertraline
Serotonin syndrome riskSt. John's wort
Serotonin syndrome riskSumatriptan
Serotonin syndrome riskTizanidine
Combined drowsinessTrazodone
Combined drowsinessVenlafaxine
Serotonin syndrome riskZolpidem
Extra drowsiness and slowed reactions
Minor 6 interactions
A bit more drowsinessCetirizine
Doubling up on antihistaminesFexofenadine
Doubling up on antihistaminesLoratadine
Doubling up on antihistaminesMelatonin
A bit more drowsinessWarfarin
Regular acetaminophen can raise INR
No known interaction found
Our rules found no interaction between NyQuil and: Acyclovir, Albuterol, Allopurinol, Amlodipine, Amoxicillin, Amoxicillin-clavulanate, Apixaban, Aripiprazole, Aspirin, Atenolol, Atorvastatin, Azithromycin, Birth control pills, Bismuth subsalicylate, Bupropion, Caffeine, Calcium carbonate, Carvedilol, Celecoxib, Cephalexin, Ciprofloxacin, Clindamycin, Clopidogrel, Colchicine, Creatine, Diclofenac, Digoxin, Doxycycline, Empagliflozin, Esomeprazole, Estradiol, Famotidine, Finasteride, Fish oil, Fluconazole, Furosemide, Glipizide, Grapefruit juice, Guaifenesin, Hydrochlorothiazide, Hydroxychloroquine, Ibuprofen, Insulin, Iron supplements, Isotretinoin, Lamotrigine, Levofloxacin, Levothyroxine, Lisinopril, Loperamide, Losartan, Magnesium, Meloxicam, Metformin, Methotrexate, Methylphenidate, Methylprednisolone, Metoprolol, Metronidazole, Montelukast, Naltrexone, Naproxen, Nicotine, Nitrofurantoin, Omeprazole, Oseltamivir, Pantoprazole, Paxlovid, Phentermine, Phenylephrine, Potassium supplements, Pravastatin, Prednisone, Probiotics, Propranolol, Pseudoephedrine, Rivaroxaban, Rosuvastatin, Semaglutide, Sildenafil, Simvastatin, Spironolactone, Sulfamethoxazole-trimethoprim, Tadalafil, Tamsulosin, Tirzepatide, Topiramate, Turmeric, Valacyclovir, Vitamin D, Zinc.
Add at least two medicines, supplements or alcohol.
Sources
Source: FDA label for NyQuil on DailyMed (effective 2026-06), plus the labels of each interacting medicine.
This list covers the 147 medicines and substances in our database. It is not a complete list of every possible interaction. Always tell your doctor and pharmacist about every medicine, supplement and herbal product you take.