Zyrtec and Complex partial seizures - a phase IV clinical study of FDA data

Summary:

Complex partial seizures is reported as a side effect among people who take Zyrtec (cetirizine hydrochloride), especially for people who are female, 40-49 old, have been taking the drug for < 1 month also take Keppra, and have Depression.

The phase IV clinical study analyzes which people have Complex partial seizures 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 Complex partial seizures?

Complex partial seizures (epileptic seizure) is found to be associated with 216 drugs and 440 conditions by eHealthMe. Check the latest studies of Complex partial seizures.

eHealthMe: drug outcomes in the real world

eHealthMe runs one of the largest post-marketing drug safety studies in the world. We study millions of patients and 5,000 more each day. Our data-driven phase IV clinical trials have been referenced on 800+ peer-reviewed medical publications including The Lancet, Mayo Clinic Proceedings, and Nature. Tools to study our phase IV findings are available to the public, anonymous and free >>>.

On Sep, 02, 2026

109,528 people reported to have side effects when taking Zyrtec.
Among them, 19 people (0.02%) have Complex partial seizures.

Could Zyrtec cause Complex partial seizures?

Among these 19 people:

How long have people been on Zyrtec when they have Complex partial seizures? *

What is the gender of people who have Complex partial seizures when taking Zyrtec? *

female: 78.95 %
male: 21.05 %

What is the age of people who have Complex partial seizures when taking Zyrtec? *

What are other drugs people take besides Zyrtec? *

What are other side effects people have besides Complex partial seizures? *

Dizziness: 4 people, 21.05%
Simple Partial Seizures (seizures which affect only a small region of the brain): 3 people, 15.79%
Fall: 3 people, 15.79%
Convulsion (muscles contract and relax rapidly and repeatedly, resulting in an uncontrolled shaking of the body): 3 people, 15.79%
Transient Ischaemic Attack (a transient episode of neurologic dysfunction caused by ischemia (loss of blood flow)): 3 people, 15.79%
Drowsiness: 2 people, 10.53%
Fatigue (feeling of tiredness): 2 people, 10.53%
Overdose: 2 people, 10.53%
Confusional State: 2 people, 10.53%
Migraine (headache): 2 people, 10.53%

What are the existing conditions these people have? *

Depression: 4 people, 21.05%
Sleep Disorder: 2 people, 10.53%
Petit Mal Epilepsy (absence seizure): 2 people, 10.53%
Narcolepsy (brain's inability to regulate sleep-wake cycles normally): 2 people, 10.53%
Multiple Allergies (allergy to multiple agents): 2 people, 10.53%
Epilepsy (common and diverse set of chronic neurological disorders characterized by seizures): 2 people, 10.53%
Temporal Lobe Epilepsy (a term that refers to a condition where seizures are generated in the portion of the brain called the temporal lobe): 1 person, 5.26%
Seizures (abnormal excessive or synchronous neuronal activity in the brain): 1 person, 5.26%
Osteoarthritis (a joint disease caused by cartilage loss in a joint): 1 person, 5.26%
Multiple Sclerosis (a nervous system disease that affects your brain and spinal cord. it damages the myelin sheath): 1 person, 5.26%

* Approximation only. Some reports may have incomplete information.

Do you take Zyrtec and have Complex partial seizures?

- Check whether Complex partial seizures 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 Complex partial seizures:

Complex partial seizures (216 drugs)

Browse all the conditions that are associated with Complex partial seizures:

Complex partial seizures (440 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.