Premproconjugated estrogens + medroxyprogesterone
23,340 adverse event reports submitted to the FDA (2000–2026)
Top Reported Adverse Events
The most frequently reported events in association with Prempro in the FAERS database. These are events reported by patients taking this medication, not necessarily caused by it. A single report may include multiple events.
Show these terms with plain-language definitions
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Breast Cancer 7,884 reports
A cancer that forms in the tissue of the breast. It may appear in reports as a condition being treated or monitored.
Full definition in the glossary →Breast Cancer Female 5,786 reports
A report of breast cancer in a female patient. It may appear in reports as a condition being treated or monitored, not necessarily as a reaction.
Full definition in the glossary →Breast Cancer Metastatic 1,506 reports
Breast cancer that has spread to other parts of the body. It may appear in reports as a condition being treated.
Full definition in the glossary →Drug Ineffective 724 reports
A report that the medication did not work as expected for the person taking it. This is a reporting category, not a sign the drug is defective. It simply means someone felt it was not helping their condition.
Full definition in the glossary →Cerebrovascular Accident 501 reports
The medical term for a stroke, which happens when blood flow to part of the brain is interrupted.
Full definition in the glossary →Depression 472 reports
A persistent low mood, loss of interest, or feelings of sadness. If you are struggling, the 988 Suicide and Crisis Lifeline (call or text 988 in the US) is available 24 hours a day.
Full definition in the glossary → See all drugs reporting this event →Headache 416 reports
Pain in the head or upper neck.
Full definition in the glossary → See all drugs reporting this event →Anxiety 409 reports
A feeling of worry, nervousness, or unease.
Full definition in the glossary → See all drugs reporting this event →Nausea 406 reports
The feeling of sickness in your stomach that often comes before vomiting.
Full definition in the glossary → See all drugs reporting this event →Deep Vein Thrombosis 394 reports
A blood clot that forms in a deep vein, usually in the leg. It can be serious if the clot travels to the lungs.
Full definition in the glossary →Fatigue 385 reports
Extreme tiredness or lack of energy that does not improve with rest.
Full definition in the glossary → See all drugs reporting this event →Hot Flush 384 reports
A sudden feeling of heat, often in the face and upper body, sometimes with sweating. Often called a hot flash in American English.
Full definition in the glossary → See all drugs reporting this event →Myocardial Infarction 374 reports
The medical term for a heart attack.
Full definition in the glossary →- Oestrogen Receptor Assay Positive 374 reports
Insomnia 373 reports
Difficulty falling asleep or staying asleep.
Full definition in the glossary → See all drugs reporting this event →
Ranked by frequency of reports, not severity. The most-reported event is not necessarily the most dangerous or the most common in patients taking this drug.
Who Is Reporting
Demographics of patients in FAERS reports that included this information. Not all reports include patient demographics.
By Sex
View reporter sex data as a table
| Sex | Reports |
|---|---|
| Female | 22,778 |
| Unknown | 35 |
| Male | 21 |
By Age Group
View age group data as a table
| Age group | Reports |
|---|---|
| 0-17 | 10 |
| 18-34 | 29 |
| 35-49 | 759 |
| 50-64 | 6,249 |
| 65-74 | 1,841 |
| 75+ | 439 |
This shows who filed reports, reflecting who takes this drug and who tends to report, not who is at greatest risk.
Reported Outcomes
Outcomes recorded in FAERS reports that included Prempro. A single report may involve multiple reactions, each with a different outcome. These categories are defined by FDA reporting guidelines, not by PillSignal.
View outcome data as a table
| Outcome | Reports |
|---|---|
| Other Serious | 18,756 |
| Non-Serious | 3,567 |
| Hospitalization | 2,735 |
| Death | 643 |
| Disability | 584 |
| Life-Threatening | 143 |
Serious outcomes are far more likely to be reported than mild ones, so this overstates how often outcomes are serious. A recorded death does not mean the drug caused it.
Report Volume Over Time
Number of FAERS reports received per quarter for Prempro. Changes in volume may reflect shifts in prescribing rates, media attention, or reporting behavior, not changes in the medication's safety profile.
View report trend as a table
| Year | Reports |
|---|---|
| 2000 | 1 |
| 2002 | 1 |
| 2004 | 1,602 |
| 2005 | 1,529 |
| 2006 | 1,381 |
| 2007 | 948 |
| 2008 | 1,913 |
| 2009 | 4,408 |
| 2010 | 5,903 |
| 2011 | 1,202 |
| 2012 | 741 |
| 2013 | 482 |
| 2014 | 353 |
| 2015 | 383 |
| 2016 | 390 |
| 2017 | 306 |
| 2018 | 233 |
| 2019 | 315 |
| 2020 | 357 |
| 2021 | 218 |
| 2022 | 253 |
| 2023 | 154 |
| 2024 | 129 |
| 2025 | 118 |
| 2026 (partial) | 20 |
The steep increase around 2004 reflects the FDA's move to electronic submission, not a change in this drug's safety. Trends track reporting volume, not risk.
Medications commonly reported with Prempro
In FDA adverse event reports that mention Prempro, these medications appeared most often in the same report.
- Estradiol (2,031 reports)
- Levothyroxine (1,112 reports)
- Estradiol % (651 reports)
- Estradiol Transdermal (651 reports)
- Aspirin (566 reports)
This reflects co-occurrence in submitted reports, not evidence of drug interaction or combined risk. People often report several medications taken for the same condition or for unrelated reasons. Talk to a doctor or pharmacist about your specific medications.
Related Drugs
Other medications with similar adverse event profiles in FDA FAERS reports.
Data Source
This data is sourced from the FDA's Adverse Event Monitoring System (AEMS), formerly FAERS, via the OpenFDA API. PillSignal is not affiliated with the FDA.
View this data on the FDA website →Data last updated: June 2026