Can you take NyQuil and DayQuil together?
By
Dr Drielli Vital-Fujii (PhD)
Author bio
Dr Drielli Vital-Fujii, PhD, is a Pharmacist with expertise in Drug Design and Development, Enzymes, Molecular Modelling, and Photodynamic Therapy. She writes and reviews content on these topics.
Dr Drielli Vital-Fujii’s Highlights:
- Postdoctoral fellow at the Department of Biochemistry at the University of São Paulo, emphasizing therapy of neglected diseases using light.
- PhD in Pharmaceutical Sciences focusing on drug design and development at the Faculty of Pharmaceutical Sciences of the University of São Paulo.
- Six months as an international researcher at the Center for Discovery and Innovation in Parasitic Diseases (University of California San Diego)
- Master’s degree in Pharmaceutical Sciences focusing on drug design and development at the Faculty of Pharmaceutical Sciences of the University of São Paulo.
- Bachelor of Pharmacy at the University of Mogi das Cruzes – São Paulo / Brazil
Professional Experience:
2012 – 2018 Project manager at University of São Paulo – Pharmacy Department
Dr Drielli Vital-Fujii has worked with computational studies, synthesis, biological evaluation, design, and development of new inhibitor candidates for Chagas Disease and Leishmaniasis.
2017 – 2017 International research fellow at University of California San Diego Skaggs School of Pharmacy and Pharmaceutical Sciences – Center for Discovery and Innovation in Parasitic Diseases.
She used Virtual Screening (VS) and High-Throughput Screening (HTS) Integration in the Discovery of new drugs against neglected tropical diseases (NTDs).
2018 – 2019 Faculdades Oswaldo Cruz
Dr Drielli Vital-Fujii was a professor in the Faculty of Pharmacy, teaching the subjects of Pharmaceutical Chemistry and Drug Development.
2019 – 2021 Researcher in Biochemistry University of São Paulo – Biochemistry Department
She applied Photodynamic Therapy in Leishmaniasis Treatment, mentored undergraduate students in scientific activities, and wrote, executed, translated, and reported scientific projects with funding agencies.
2023-2023 UniPiaget – University Center.
Dr Drielli Vital-Fujii was a Biology, Nutrition, Physiotherapy, and Pharmacy professor.
Education:
2018 -2021 Postdoctoral at the Department of Biochemistry at the University of São Paulo
2013 -2018 PhD of Science: Drugs and Medicines at Department of Pharmacy at University of São Paulo
2012 -2013 M.Sc. of Sciences: Drugs and Medicines at the Department of Pharmacy at the University of São Paulo
2005-2008 Bachelor of Pharmacy at the University of Mogi das Cruzes
The leading publications of Dr Drielli Vital-Fujii are:
Vital-Fujii, D.G, Baptista, M.S. (2021). Progress in the photodynamic therapy treatment of Leishmaniasis. Brazilian Journal of Medical and Biological Research, 54, 1-11.
Gatti, F. M., Gomes, R.A., da Fonseca, A.L., Lima, E.J.C., Vital-Fujii, D.G., Taranto, A.G., Varotti, F.P., Trossini, G.H.G. (2020). Antiplasmodial activity of sulfonylhydrazones: in vitro and in silico approaches. Future medicinal chemistry, 13, 233-250.
Silva, E.J., Bezerra-Souza, A., Passero, L.F., Laurenti, M.D., Ferreira, G.M., Fujii, D.G.V., et al. (2018). Synthesis, leishmanicidal activity, structural descriptors and structure-activity relationship of quinoline derivatives. Future medicinal chemistry, 10, 2069-2085.
Leite, F.H.A., Froes, T.Q., da Silva, S.G., de Souza, E.I.M., Vital-Fuji,i D.G., Trossini, G.H.G., et al. (2017). An integrated approach towards the discovery of novel non-nucleoside Leishmania major pteridine reductase 1 inhibitors. European Journal of Medicinal Chemistry, 132, 322-332.
Vital, D.G., Damasceno, F.S., Rapado, L.N., Silber, A.M., Vilella, F.S., Ferreira, R.S., et al. (2017). Application of bioisosterism in design of the semicarbazone derivatives as cruzain inhibitors: a theoretical and experimental study. Journal of Biomolecular Structure and Dynamics, 35, 1244–1259.
Mello, J. F.R., Gomes, R.A., Vital-Fujii, D.G., Ferreira, G.M., Trossini, G.H.G. (2017). Fragment-based drug discovery as alternative strategy to the drug development for neglected diseases. Chemical Biology & Drug Design, 90, 1067-1078.
Pantaleao, S.Q., Fujii, D.G.V., Maltarollo, V.G., da C. Silva, D., Trossini, G.H.G., Weber, K.C., et al. (2017). The Role of QSAR and Virtual Screening Studies in Type 2 Diabetes Drug Discovery. Medicinal Chemistry, 13, 706-720.
Vital, D., Arribas, M., Trossini, G. (2014). Molecular Modeling and Docking Application to Evaluate Cruzain Inhibitory Activity by Chalcones and Hydrazides. Letters in Drug Design and Discovery, 11, 249-255.
Blau, L., Menegon, R.F., Trossini, G.H.G., Molino, J.V.D., Vital, D.G., Cicarelli, R.M.B., et al. (2013). Design, synthesis and biological evaluation of new aryl thiosemicarbazone as antichagasic candidates. European Journal of Medicinal Chemistry, 67, 142-151.
You can view some of Dr Drielli’s work below and links to her professional profile.
Orcid: https://orcid.org/0000-0001-9270-0466
Research Gate: https://www.researchgate.net/profile/Drielli-Gomes-Vital-Fujii
Scopus: https://www.scopus.com/authid/detail.uri?authorId=55829534000
Google Scholar: https://scholar.google.com/citations?user=F9U50AEAAAAJ&hl=pt-BR
Linkedin: linkedin.com/in/driellivital
Escavador: https://www.escavador.com/sobre/6101380/drielli-gomes-vital
CDIPD: https://cdipd.org/index.php/about-us/visiting-scientists
Can you take NyQuil and DayQuil together?
No, it is not appropriate to take both NyQuil and DayQuil together or at the same time. This is because they both contain similar active ingredients and taking them both at the same time would result in an overdose and will cause disturbing side effects.
However, you can take NyQuil and DayQuil on the same day. Just take DayQuil in the daytime and NyQuil at nighttime, just as they are intended to be used.
Let’s look at the ingredients of NyQuil and DayQuil to help you understand the dangers associated with using these two at the same time.
List of ingredients
| NyQuil | DayQuil |
| Acetaminophen | Acetaminophen |
| Dextromethorphan | Dextromethorphan |
| Doxylamine | Phenylephrine |
Acetaminophen works as a painkiller and fever reducer. Dextromethorphan is an antitussive agent which helps suppress cough. The difference between NyQuil and DayQuil is the third ingredient, that’s Doxylamine for NyQuil and Phenylephrine for DayQuil.
Doxylamine is an antihistamine which controls allergy symptoms. Phenylephrine is a decongestant.
What are the dangers associated with the use of NyQuil and DayQuil?
Taking NyQuil and DayQuil at the same time can have 2 major concerns.
- Acetaminophen overdose
- Dextromethorphan overdose
Acetaminophen overdose
Acetaminophen, although it is considered the safest painkiller, can cause a number of disturbing side effects if misused (1). Acetaminophen is hepatotoxic in nature, which means it affects your liver and damages the hepatocytes or liver cells.
Although it does not happen with a single overdose, long-term use of high-dose Acetaminophen can significantly affect your liver function. If you’re an alcoholic, the effects could be life-threatening. This is why you should not pair DayQuil and NyQuil together, or pair them with other OTC Products that contain Acetaminophen, like Tylenol.
Dextromethorphan overdose
Overdosing on Dextromethorphan is another concern as this ingredient is also common in both NyQuil and DayQuil. Dextromethorphan is a cough suppressant and its overdose can cause side effects like (2)
- Drowsiness
- Dizziness
- Nervousness
- Confusion
- Stomach pain
- Nausea
- Vomiting
- Lightheadedness
- Skin allergy
Is there a way to use NyQuil and DayQuil together?
As I just stated, NyQuil and DayQuil can not be taken at the same time, but they can be taken on the same day by changing the time of these meds. DayQuil, as its name indicates, should be used during the daytime.
Whereas, NyQuil should be used at night. Even if you’re not taking it that way or you have forgotten your morning dose, just make sure there is a 4-6 hour gap between the administration of these two meds. A lesser gap will most likely be included as an overdose.
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References
1.-
Agrawal S, Khazaeni B. Acetaminophen Toxicity. 2023 Feb 12. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan–. PMID: 28722946. Available from: https://www.ncbi.nlm.nih.gov/books/NBK441917/
2.-
Journey JD, Agrawal S, Stern E. Dextromethorphan Toxicity. 2022 Jun 27. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan–. PMID: 30860737. Available from: https://www.ncbi.nlm.nih.gov/books/NBK538502/
