1. Home
  2. Analysis
  3. Opana
  4. Norflex

Opana vs. Norflex: side effect and effectiveness comparison (a real world drug study)

Summary:

We compare the side effects and drug effectiveness of Opana and Norflex. The phase IV clinical study is created by eHealthMe based on reports (from sources including the FDA) of 51,792 people who take Opana and Norflex, and is updated regularly.

What is Opana?

Opana has active ingredients of oxymorphone hydrochloride. It is often used in pain. eHealthMe is studying from 40,340 Opana users. Check the latest studies of Opana.

What is Norflex?

Norflex has active ingredients of orphenadrine citrate. It is often used in muscle spasms. eHealthMe is studying from 1,951 Norflex users. Check the latest studies of Norflex.

On Jul, 07, 2026

51,792 people who take Opana and Norflex are studied.

Opana vs Norflex drug comparison reports.

Drugs being compared in this study:

  • Opana (oxymorphone hydrochloride)
  • Norflex (orphenadrine citrate)

Most common side effects of the drugs, overall:

Click here to view

Most common side effects of the drugs, in long term (1+ years) use:

Click here to view

Drug effectiveness:

Opana:

  • not at all: 4.76 %
  • somewhat: 23.81 %
  • moderate: 41.37 %
  • high: 20.54 %
  • very high: 9.52 %

Norflex:

  • not at all: 8.5 %
  • somewhat: 27.45 %
  • moderate: 34.64 %
  • high: 22.88 %
  • very high: 6.54 %

Want to compare Opana with Norflex?

- Personalize this study to your gender and age (0-99+)

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.

Related studies

Alternative drugs to, pros and cons of:

Browse all side effects of Opana:

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 Norflex:

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

How the study uses the data?

The study is based on oxymorphone hydrochloride and orphenadrine citrate (the active ingredients of Opana and Norflex, respectively). Other drugs that have the same active ingredients (e.g. generic drugs or brand names) are also considered. Dosage of drugs is not considered in the study.

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.

Recent studies on eHealthMe:

© 2026 eHealthMe.com. All rights reserved. Use of this site constitutes acceptance of eHealthMe.com's terms of service and privacy policy.