Benadryl and Angle closure glaucoma - a phase IV clinical study of FDA data

Summary:

Angle closure glaucoma is reported as a side effect among people who take Benadryl (diphenhydramine hydrochloride), especially for people who are female, 50-59 old, have been taking the drug for < 1 month also take Lexapro, and have Drug hypersensitivity.

The phase IV clinical study analyzes which people have Angle closure glaucoma when taking Benadryl. It is created by eHealthMe based on reports of 100,139 people who have side effects when taking Benadryl from the FDA, and is updated regularly.

What is Benadryl?

Benadryl has active ingredients of diphenhydramine hydrochloride. It is often used in allergies. eHealthMe is studying from 104,955 Benadryl users. Check the latest studies of Benadryl.

What is Angle closure glaucoma?

Angle closure glaucoma (term used for several ocular diseases that ultimately result in increased intraocular pressure (iop) and decreased visual acuity) is found to be associated with 207 drugs and 481 conditions by eHealthMe. Check the latest studies of Angle closure glaucoma.

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 Aug, 24, 2026

100,139 people reported to have side effects when taking Benadryl.
Among them, 11 people (0.01%) have Angle closure glaucoma.

Could Benadryl cause Angle closure glaucoma?

Among these 11 people:

How long have people been on Benadryl when they have Angle closure glaucoma? *

What is the gender of people who have Angle closure glaucoma when taking Benadryl? *

female: 100 %
male: 0.0 %

What is the age of people who have Angle closure glaucoma when taking Benadryl? *

What are other drugs people take besides Benadryl? *

What are other side effects people have besides Angle closure glaucoma? *

Foot Fracture: 2 people, 18.18%
Impaired Gastric Emptying: 2 people, 18.18%
Drug Ineffective: 2 people, 18.18%
Drug Intolerance (drug sensitivity): 2 people, 18.18%
Fall: 2 people, 18.18%
Glucose Tolerance Impaired (blood glucose is raised beyond normal levels, but not high enough to warrant a diabetes diagnosis): 2 people, 18.18%
High Blood Cholesterol: 2 people, 18.18%
Asthma: 2 people, 18.18%
Infusion Related Reaction: 2 people, 18.18%
Optic Neuritis (optic nerve inflammation): 2 people, 18.18%

What are the existing conditions these people have? *

Tremor (trembling or shaking movements in one or more parts of your body): 2 people, 18.18%
Primary Progressive Multiple Sclerosis (primary progressive inflammatory disease in which the insulating covers of nerve cells in the brain and spinal cord are damaged): 2 people, 18.18%
Optic Neuritis (optic nerve inflammation): 2 people, 18.18%
Migraine (headache): 2 people, 18.18%
Fatigue (feeling of tiredness): 2 people, 18.18%
Drug Hypersensitivity: 2 people, 18.18%
Urticaria (rash of round, red welts on the skin that itch intensely): 1 person, 9.09%
Stress And Anxiety: 1 person, 9.09%
Sleep Disorder: 1 person, 9.09%
Narcolepsy (brain's inability to regulate sleep-wake cycles normally): 1 person, 9.09%

* Approximation only. Some reports may have incomplete information.

Do you take Benadryl and have Angle closure glaucoma?

- Check whether Angle closure glaucoma 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 Benadryl:

Benadryl (104,955 reports)

Browse all side effects of Benadryl:

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 Angle closure glaucoma:

Angle closure glaucoma (207 drugs)

Browse all the conditions that are associated with Angle closure glaucoma:

Angle closure glaucoma (481 conditions)

How the study uses the data?

The study uses data from the FDA. It is based on diphenhydramine hydrochloride (the active ingredients of Benadryl) and Benadryl (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.