Zyrtec and Electrocardiogram t wave inversion - a phase IV clinical study of FDA data

Summary:

Electrocardiogram t wave inversion is reported as a side effect among people who take Zyrtec (cetirizine hydrochloride), especially for people who are female, 60+ old, also take Synthroid, and have High blood pressure.

The phase IV clinical study analyzes which people have Electrocardiogram t wave inversion when taking Zyrtec. It is created by eHealthMe based on reports of 109,528 people who have side effects when taking Zyrtec 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 114,620 Zyrtec users. Check the latest studies of Zyrtec.

What is Electrocardiogram t wave inversion?

Electrocardiogram t wave inversion is found to be associated with 417 drugs and 762 conditions by eHealthMe. Check the latest studies of Electrocardiogram t wave inversion.

On Aug, 12, 2026

109,528 people reported to have side effects when taking Zyrtec.
Among them, 23 people (0.02%) have Electrocardiogram t wave inversion.

Could Zyrtec cause Electrocardiogram t wave inversion?

Among these 23 people:

What is the gender of people who have Electrocardiogram t wave inversion when taking Zyrtec? *

female: 80.95 %
male: 19.05 %

What is the age of people who have Electrocardiogram t wave inversion when taking Zyrtec? *

What are other drugs people take besides Zyrtec? *

What are other side effects people have besides Electrocardiogram t wave inversion? *

Nausea (feeling of having an urge to vomit): 10 people, 43.48%
Heart Attack: 9 people, 39.13%
Chest Pain: 9 people, 39.13%
Dyspnea (difficult or laboured breathing): 8 people, 34.78%
Sinus Bradycardia (an unusually slow heartbeat due to heart disease): 6 people, 26.09%
Weakness: 6 people, 26.09%
Nausea And Vomiting: 5 people, 21.74%
High Blood Cholesterol: 5 people, 21.74%
Dizziness: 5 people, 21.74%
Coronary Heart Disease (narrowing or blockage of the coronary arteries): 5 people, 21.74%

What are the existing conditions these people have? *

High Blood Pressure: 4 people, 17.39%
Osteoarthritis (a joint disease caused by cartilage loss in a joint): 3 people, 13.04%
Arrhythmias (irregular heartbeat): 2 people, 8.70%
Pituitary-Dependent Cushing's Syndrome (pituitary dependent hypercortisolism): 2 people, 8.70%
High Blood Cholesterol: 2 people, 8.70%
Hypersensitivity: 1 person, 4.35%
Chronic Graft Versus Host Disease (immune cells attack the host's body cells after transplant): 1 person, 4.35%
Deep Venous Thrombosis (blood clot in a major vein that usually develops in the legs and/or pelvis): 1 person, 4.35%
Depression: 1 person, 4.35%
Dry Eyes (lack of adequate tears): 1 person, 4.35%

* Approximation only. Some reports may have incomplete information.

Do you take Zyrtec and have Electrocardiogram t wave inversion?

- Check whether Electrocardiogram t wave inversion is associated with a drug or a condition
- Predict drug outcomes for up to one year with AI
- Get an AI agent to monitor your drugs continuously

Related studies:

Effectiveness of, long term effects of, and alternative drugs to Zyrtec:

Zyrtec (114,620 reports)

Browse all side effects of Zyrtec:

a b c d e f g h i j k l m n o p q r s t u v w x y z

Browse all the drugs that are associated with Electrocardiogram t wave inversion:

Electrocardiogram t wave inversion (417 drugs)

Browse all the conditions that are associated with Electrocardiogram t wave inversion:

Electrocardiogram t wave inversion (762 conditions)

How the study uses the data?

The study uses data from the FDA. It is based on cetirizine hydrochloride (the active ingredients of Zyrtec) and Zyrtec (the brand name). 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.