Zyrtec and Flagyl drug interactions - a phase IV clinical study of FDA data

Summary:

Drug interactions are reported among people who take Zyrtec (cetirizine hydrochloride) and Flagyl (metronidazole). Common drug interactions include dyspnoea among females and fatigue among males.

The phase IV clinical study analyzes what interactions people have when they take Zyrtec and Flagyl. It is created by eHealthMe based on reports of 479 people who take the same drugs from the FDA, and is updated regularly.

What is Zyrtec?

Zyrtec has active ingredients of cetirizine hydrochloride. It is often used in allergies. eHealthMe is studying from 114,618 Zyrtec users. Check the latest studies of Zyrtec.

What is Flagyl?

Flagyl has active ingredients of metronidazole. It is often used in vaginitis bacterial. eHealthMe is studying from 25,897 Flagyl users. Check the latest studies of Flagyl.



On Mar, 31, 2026

479 people who take Zyrtec and Flagyl together, and have interactions are studied.

Zyrtec and Flagyl drug interactions.

What are the common drug interactions of Zyrtec and Flagyl, by gender? *

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What are the common drug interactions of Zyrtec and Flagyl, by age (0-1 to 60+)? *

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What are the existing conditions these people have? *

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* Approximation only. Some reports may have incomplete information.

Do you take Zyrtec and Flagyl?

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Related studies:

Effectiveness of, side effects of, and alternative drugs to the 2 drugs:

Browse all drug interactions of Zyrtec and Flagyl:

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Sub-studies by gender and age:

Female: 0-1 2-9 10-19 20-29 30-39 40-49 50-59 60+

Male: 0-1 2-9 10-19 20-29 30-39 40-49 50-59 60+

Browse all side effects of Zyrtec:

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Browse all side effects of Flagyl:

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Browse all interactions between Zyrtec and drugs from A to Z:

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Browse all interactions between Flagyl and drugs from A to Z:

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How the study uses the data?

The study uses data from the FDA. It is based on cetirizine hydrochloride and metronidazole (the active ingredients of Zyrtec and Flagyl, respectively), and Zyrtec and Flagyl (the brand names). Other drugs that have the same active ingredients (e.g. generic drugs) are not considered. Dosage of drugs is not considered in the study.

How to use the study?

DO NOT STOP MEDICATIONS without first consulting your doctor. If there are any serious or long term adverse effects discovered in the study, discuss the study with your doctor to ensure that proper medication management will be in place if applicable.

Who is eHealthMe?

With medical big data and proven AI/ML algorithms, eHealthMe provides a platform for everyone to run phase IV clinical trials. We study millions of patients and 5,000 more each day. Results of our real-world drug study have been referenced on 800+ peer-reviewed medical publications, including The Lancet, Mayo Clinic Proceedings, and Nature. Our analysis results are available to researchers, health care professionals, patients (testimonials), and software developers (open API).

WARNING, DISCLAIMER, USE FOR PUBLICATION

WARNING: Please DO NOT STOP MEDICATIONS without first consulting a physician since doing so could be hazardous to your health.

DISCLAIMER: All material available on eHealthMe.com is for informational purposes only, and is not a substitute for medical advice, diagnosis, or treatment provided by a qualified healthcare provider. All information is observation-only. Our phase IV clinical studies alone cannot establish cause-effect relationship. Different individuals may respond to medication in different ways. Every effort has been made to ensure that all information is accurate, up-to-date, and complete, but no guarantee is made to that effect. The use of the eHealthMe site and its content is at your own risk.

If you use this eHealthMe study on publication, please acknowledge it with a citation: study title, URL, accessed date.



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