Zanaflex and Angioedema - a phase IV clinical study of FDA data


Angioedema is found among people who take Zanaflex, especially for people who are female, 60+ old.

The phase IV clinical study analyzes which people take Zanaflex and have Angioedema. It is created by eHealthMe based on reports of 15,351 people who have side effects when taking Zanaflex from the FDA, and is updated regularly. You can use the study as a second opinion to make health care decisions.

Phase IV trials are used to detect adverse drug outcomes and monitor drug effectiveness in the real world. With medical big data and AI algorithms, eHealthMe is running millions of phase IV trials and makes the results available to the public. Our original studies have been referenced on 600+ medical publications including The Lancet, Mayo Clinic Proceedings, and Nature.

On Mar, 24, 2023

15,351 people reported to have side effects when taking Zanaflex.
Among them, 11 people (0.07%) have Angioedema.

What is Zanaflex?

Zanaflex has active ingredients of tizanidine hydrochloride. It is often used in muscle spasms. eHealthMe is studying from 16,478 Zanaflex users for its effectiveness, alternative drugs and more.

What is Angioedema?

Angioedema (rapid swelling of the dermis) is found to be associated with 2,476 drugs and 1,979 conditions by eHealthMe.

Number of Zanaflex and Angioedema reports submitted per year:

Could Zanaflex cause Angioedema?

Gender of people who have Angioedema when taking Zanaflex *:

  • female: 81.82 %
  • male: 18.18 %

Age of people who have Angioedema when taking Zanaflex *:

  • 0-1: 0.0 %
  • 2-9: 0.0 %
  • 10-19: 0.0 %
  • 20-29: 0.0 %
  • 30-39: 42.86 %
  • 40-49: 14.29 %
  • 50-59: 0.0 %
  • 60+: 42.86 %

Common drugs people take besides Zanaflex *:

  1. Neurontin: 5 people, 45.45%
  2. Ambien: 4 people, 36.36%
  3. Synthroid: 3 people, 27.27%
  4. Lasix: 3 people, 27.27%
  5. Plaquenil: 3 people, 27.27%
  6. Prozac: 3 people, 27.27%
  7. Nexium: 3 people, 27.27%
  8. Benlysta: 3 people, 27.27%
  9. Lortab: 3 people, 27.27%
  10. Axid: 2 people, 18.18%

Common side effects people have besides Angioedema *:

  1. Drowsiness: 5 people, 45.45%
  2. Back Pain: 5 people, 45.45%
  3. Malaise (a feeling of general discomfort or uneasiness): 5 people, 45.45%
  4. Gait Disturbance: 5 people, 45.45%
  5. Joint Pain: 4 people, 36.36%
  6. Asthma: 4 people, 36.36%
  7. Swelling: 4 people, 36.36%
  8. Joint Lock: 4 people, 36.36%
  9. Rashes (redness): 4 people, 36.36%
  10. Itching: 3 people, 27.27%

Common conditions people have *:

  1. Asthma: 3 people, 27.27%
  2. Systemic Lupus Erythematosus (an autoimmune disease, which means the body's immune system mistakenly, attacks healthy tissue): 3 people, 27.27%
  3. Back Pain: 2 people, 18.18%
  4. Breakthrough Pain: 2 people, 18.18%
  5. Cluster Headache (one-sided head pain with tearing): 2 people, 18.18%
  6. Gastroesophageal Reflux Disease (a condition in which stomach contents leak backward from the stomach into the oesophagus): 2 people, 18.18%
  7. Gout (uric acid crystals building up in the body): 2 people, 18.18%
  8. Headache (pain in head): 2 people, 18.18%
  9. Thyroid Diseases: 2 people, 18.18%
  10. Oxygen Saturation Decreased: 2 people, 18.18%

* Approximation only. Some reports may have incomplete information.

Do you take Zanaflex and have Angioedema?

Check whether Angioedema is associated with a drug or a condition

How to use the study?

You can discuss the study with your doctor, to ensure that all drug risks and benefits are fully discussed and understood.

Related publications that referenced our studies

Related studies

How severe was Angioedema and when was it recovered:

Expand to all the drugs that have ingredients of tizanidine hydrochloride:

Alternative drugs to, pros and cons of Zanaflex:

Common Zanaflex side effects:

Browse all side effects of Zanaflex:

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

Angioedema treatments and more:

COVID vaccines that are related to Angioedema:

Common drugs associated with Angioedema:

All the drugs that are associated with Angioedema:

Common conditions associated with Angioedema:

All the conditions that are associated with Angioedema:

How the study uses the data?

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

Who is eHealthMe?

With medical big data and proven AI 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 600+ 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: Please DO NOT STOP MEDICATIONS without first consulting a physician since doing so could be hazardous to your health.

DISCLAIMER: All material available on 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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