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Zaditor and Viagra drug interactions - a phase IV clinical study of FDA data

Summary:

Drug interactions are reported among people who take Zaditor (ketotifen fumarate) and Viagra (sildenafil citrate). Common drug interactions include dyspnoea among males.

The phase IV clinical study analyzes what interactions people have when they take Zaditor and Viagra. It is created by eHealthMe based on reports of 12 people who take the same drugs from the FDA, and is updated regularly.

What is Zaditor?

Zaditor has active ingredients of ketotifen fumarate. It is often used in eye allergy. eHealthMe is studying from 4,448 Zaditor users. Check the latest studies of Zaditor.

What is Viagra?

Viagra has active ingredients of sildenafil citrate. It is often used in erection problems. eHealthMe is studying from 63,865 Viagra users. Check the latest studies of Viagra.

On Jul, 12, 2026

12 people who take Zaditor and Viagra together, and have interactions are studied.

Zaditor and Viagra drug interactions.

What are the common drug interactions of Zaditor and Viagra, by gender? *:

female:

n/a

male:

  1. Dyspnoea (difficult or laboured respiration)
  2. Spinal column stenosis (narrowing of spinal column)
  3. Aortic arteriosclerosis (hardening of the aortic arteries)
  4. Aortic dilatation
  5. Asthenia (weakness)
  6. Bone disorder
  7. Death
  8. Decreased interest
  9. Deformity (disfigurement)
  10. Emotional distress

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

0-1:

n/a

2-9:

n/a

10-19:

n/a

20-29:

n/a

30-39:

n/a

40-49:

n/a

50-59:

n/a

60+:

  1. Dyspnoea (difficult or laboured respiration)
  2. Spinal column stenosis (narrowing of spinal column)
  3. Aortic arteriosclerosis (hardening of the aortic arteries)
  4. Aortic dilatation
  5. Asthenia (weakness)
  6. Bone disorder
  7. Cardiac failure congestive
  8. Chest discomfort
  9. Chest pain
  10. Cough

What are the existing conditions these people have? *

  1. Multiple Myeloma (cancer of the plasma cells): 7 people, 58.33%
  2. Infection: 5 people, 41.67%
  3. Hypersensitivity: 5 people, 41.67%
  4. High Blood Pressure: 5 people, 41.67%
  5. High Blood Cholesterol: 5 people, 41.67%
  6. Gout (uric acid crystals building up in the body): 5 people, 41.67%
  7. Glaucoma (increased fluid pressure in the eye with vision loss): 5 people, 41.67%
  8. Gastroesophageal Reflux Disease (a condition in which stomach contents leak backward from the stomach into the oesophagus): 5 people, 41.67%
  9. Eye Swelling: 5 people, 41.67%
  10. Diabetes: 5 people, 41.67%

* Approximation only. Some reports may have incomplete information.

Do you take Zaditor and Viagra?

- Personalize this study to your gender, age, symptoms and drugs
- Predict drug outcomes for up to one year with AI
- Get an AI agent to monitor your drugs continuously

Related studies:

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

Browse all drug interactions of Zaditor and Viagra:

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

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 Zaditor:

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 side effects of Viagra:

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 interactions between Zaditor and drugs from A to Z:

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 interactions between Viagra and drugs from A to Z:

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

Related publications that referenced our studies

How the study uses the data?

The study uses data from the FDA. It is based on ketotifen fumarate and sildenafil citrate (the active ingredients of Zaditor and Viagra, respectively), and Zaditor and Viagra (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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