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Subsys and Megace drug interactions - a phase IV clinical study of FDA data

Summary:

Drug interactions are reported among people who take Subsys (fentanyl) and Megace (megestrol acetate). Common drug interactions include death among females and atrial fibrillation among males.

The phase IV clinical study analyzes what interactions people have when they take Subsys and Megace. 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 Subsys?

Subsys has active ingredients of fentanyl. eHealthMe is studying from 9,239 Subsys users. Check the latest studies of Subsys.

What is Megace?

Megace has active ingredients of megestrol acetate. It is often used in weight loss. eHealthMe is studying from 10,095 Megace users. Check the latest studies of Megace.

On Jul, 22, 2026

12 people who take Subsys and Megace together, and have interactions are studied.

Subsys and Megace drug interactions.

What are the common drug interactions of Subsys and Megace, by gender? *:

female:

  1. Death
  2. Neoplasm progression (growth of tumour)
  3. Aspartate aminotransferase increased
  4. Blood alkaline phosphatase increased
  5. Blood bilirubin increased
  6. Blood glucose increased
  7. Blood urea increased
  8. Glomerular filtration rate decreased
  9. Lung neoplasm malignant (cancer tumour of lung)
  10. Malnutrition (a condition that results from eating a diet in which certain nutrients are lacking)

male:

  1. Atrial fibrillation (fibrillation of the muscles of the atria of the heart)
  2. Cardiac failure congestive
  3. Abdominal pain
  4. Blood albumin decreased
  5. Blood glucose increased
  6. Blood potassium decreased
  7. Blood pressure decreased
  8. Body height decreased
  9. Death
  10. Hypotension (abnormally low blood pressure)

What are the common drug interactions of Subsys and Megace, 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:

  1. Death

60+:

  1. Neoplasm progression (growth of tumour)
  2. Atrial fibrillation (fibrillation of the muscles of the atria of the heart)
  3. Blood alkaline phosphatase increased
  4. Blood bilirubin increased
  5. Blood potassium decreased
  6. Blood urea increased
  7. Diarrhoea
  8. Erythema (redness of the skin)
  9. Glomerular filtration rate decreased
  10. Hypotension (abnormally low blood pressure)

What are the existing conditions these people have? *

  1. Multiple Myeloma (cancer of the plasma cells): 6 people, 50.00%
  2. Breakthrough Pain: 5 people, 41.67%
  3. Nausea (feeling of having an urge to vomit): 1 person, 8.33%
  4. Endometrial Cancer: 1 person, 8.33%
  5. Abdominal Pain: 1 person, 8.33%

* Approximation only. Some reports may have incomplete information.

Do you take Subsys and Megace?

- 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 Subsys and Megace:

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 Subsys:

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 Megace:

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 Subsys 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 Megace 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

How the study uses the data?

The study uses data from the FDA. It is based on fentanyl and megestrol acetate (the active ingredients of Subsys and Megace, respectively), and Subsys and Megace (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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