Folic Acid
According to the FDA label: Folic acid is effective in the treatment of megaloblastic anemias due to a deficiency of folic acid (as may be seen in tropical or nontropical sprue) and in anemias of nutritional origin, pregnancy, infancy, or childhood.
244,566 adverse event reports submitted to the FDA (2003–2026)
Top Reported Adverse Events
The most frequently reported events in association with Folic Acid 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
Tap any term below for a plain-language definition.
Drug Ineffective 24,995 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 →Fatigue 23,632 reports
Extreme tiredness or lack of energy that does not improve with rest.
Full definition in the glossary → See all drugs reporting this event →Pain 23,326 reports
A general report of physical discomfort, used when no more specific location is given.
Full definition in the glossary →Arthralgia 19,728 reports
Rheumatoid Arthritis 17,716 reports
An autoimmune condition where the immune system attacks the joints, causing pain and swelling. It often appears in reports because it is a condition being treated, not always a reaction.
Full definition in the glossary →Off Label Use 17,694 reports
Using a medication for a condition or in a way that the FDA has not officially approved. This is common and often legal, and a report of it does not mean something went wrong. Doctors sometimes prescribe drugs off label based on their judgment.
Full definition in the glossary →Nausea 15,818 reports
The feeling of sickness in your stomach that often comes before vomiting.
Full definition in the glossary → See all drugs reporting this event →Headache 14,404 reports
Pain in the head or upper neck.
Full definition in the glossary → See all drugs reporting this event →Diarrhoea 14,346 reports
Loose or watery bowel movements, often frequent. Also spelled diarrhea in American English.
Full definition in the glossary → See all drugs reporting this event →Rash 13,777 reports
An area of irritated, red, or bumpy skin.
Full definition in the glossary → See all drugs reporting this event →Dyspnoea 13,398 reports
Shortness of breath or difficulty breathing. Also spelled dyspnea in American English.
Full definition in the glossary → See all drugs reporting this event →Abdominal Discomfort 11,811 reports
A general unease or mild pain in the belly area.
Full definition in the glossary →Alopecia 11,790 reports
Joint Swelling 11,671 reports
Swelling in or around a joint.
Full definition in the glossary →Condition Aggravated 11,292 reports
A report that the person's existing health condition got worse. This describes a worsening of something the person already had, not necessarily a new problem caused by the drug.
Full definition in the glossary →
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 | 154,234 |
| Male | 71,266 |
| Unknown | 340 |
By Age Group
View age group data as a table
| Age group | Reports |
|---|---|
| 0-17 | 5,604 |
| 18-34 | 12,721 |
| 35-49 | 29,221 |
| 50-64 | 52,347 |
| 65-74 | 35,981 |
| 75+ | 26,356 |
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 Folic Acid. 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 | 121,358 |
| Hospitalization | 88,526 |
| Death | 22,650 |
| Disability | 13,189 |
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 Folic Acid. 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 |
|---|---|
| 2003 | 4 |
| 2004 | 4,027 |
| 2005 | 3,947 |
| 2006 | 3,044 |
| 2007 | 3,021 |
| 2008 | 3,900 |
| 2009 | 5,193 |
| 2010 | 5,879 |
| 2011 | 7,325 |
| 2012 | 10,350 |
| 2013 | 11,130 |
| 2014 | 11,990 |
| 2015 | 14,839 |
| 2016 | 16,505 |
| 2017 | 14,722 |
| 2018 | 15,635 |
| 2019 | 16,224 |
| 2020 | 18,147 |
| 2021 | 16,630 |
| 2022 | 16,695 |
| 2023 | 14,161 |
| 2024 | 14,781 |
| 2025 | 13,635 |
| 2026 (partial) | 2,782 |
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 Folic Acid
In FDA adverse event reports that mention Folic Acid, these medications appeared most often in the same report.
- Methotrexate (107,095 reports)
- Prednisone (53,125 reports)
- Adalimumab (52,614 reports)
- Ergocalciferol (40,483 reports)
- Acetaminophen (33,442 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