Reported Reactions

Adverse event reports that FDA received

  • Search
  • Watch list

Guanfacine hydrochloride adverse event reports that FDA received

Name type
Generic name
Class
Central alpha-2 adrenergic agonist
Also reported as
Guanfacine Hcl, Guanfacine Hydrochloride Extended-Release Tablets, Guanfacine Hcl Er

What a report is

A report is not proof that the drug was the cause of the event.

FDA says:

Adverse event reports submitted to FDA do not undergo extensive validation or verification. Therefore, a causal relationship cannot be established between product and reactions listed in a report. While a suspected relationship may exist, it is not medically validated and should not be the sole source of information for clinical decision making or other assumptions about the safety or efficacy of a product. Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product.

Source: openFDA, Drug Adverse Event Overview, section "Responsible use of the data". The site read the page on . The data have the reports that FDA received through .

FDA also says:

There is no certainty that the reported event (adverse event or medication error) was actually due to the product. FDA does not require that a causal relationship between a product and event be proven, and reports do not always contain enough detail to properly evaluate an event. The information in these reports has not been scientifically or otherwise verified as to a cause and effect relationship and cannot be used to estimate the incidence of these events.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

Do not rely on openFDA to make decisions regarding medical care. While we make every effort to ensure that data is accurate, you should assume all results are unvalidated.

Source: openFDA, Response of the drug event API (meta.disclaimer). The site read the page on .

Not medical advice. This site counts what was reported to FDA. Questions about a medicine or device belong with a pharmacist or clinician.

Reports on file

From April 2004 to June 2026, FDA received 381 adverse event reports that name Guanfacine hydrochloride. In these reports the drug is a suspect or interacting product.

In the same period, 758 further reports name it only as a concomitant medicine. The counts on this page do not include these reports.

FDA received 34 reports in the 12 months to June 2026 and 34 in the 12 months before. FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

The number of people who use the product is not in the data. A count is not a rate. A count of reports is not a count of events or of patients, because one event can have more than one report.

There are many instances of duplicative reports and some reports do not contain all the necessary information.

Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of . The site read the page on .

Suspect product

FDA records each drug in a report as suspect, concomitant or interacting. This page counts the reports in which Guanfacine hydrochloride is suspect or interacting. FDA says:

Any number of the drugs may be marked as suspect if thought to be responsible for one or more of the reactions, but that information is not validated.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

Data version

openFDA FAERS release of 1 Oct 2026. Reports received through 30 Jun 2026.

Since the last update

FDA says:

Many factors can influence whether or not an event will be reported, such as the time a product has been marketed and publicity about an event.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

The information in these reports cannot be used to estimate the incidence (occurrence rates) of the events reported.

Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of . The site read the page on .

No update is on record for this page. The record starts when FDA adds the reports of July to September 2026.

  • In April to June 2026, FDA received 14 reports that name Guanfacine hydrochloride.
  • In January to March 2026, FDA received 9.
  • In April to June 2025, FDA received 12.

April to June 2026 is the latest closed quarter in the data. A closed quarter is a quarter for which the FDA files have most of the reports.

All updatesFeed of updates (RSS)

Reaction lookup

These are the reaction terms that the reports record, with the number of reports for each term. Type a term or a plain word to find its count.

What this list leaves out

The table lists the 35 reaction terms that 5 or more reports record. A term with fewer than 5 reports is not in the table.

This list is partial.

It covers 232 of the 381 reports (60.9%).

The site keeps reaction terms only for years in which the drug has 12 or more reports.

So a count in the table can be lower than the count of FDA.

The table shows all 35 terms.

Reaction terms in the reports that name Guanfacine hydrochloride, most reports first
Reaction term (MedDRA) and plain meaningReportsShare of the 381 reports
Drug ineffectivethe medicine did not work as expected348.9%
Bradycardiaslow heart rate236%
Off label useused for a purpose or in a way not on the label236%
Somnolencedrowsiness205.2%
Hypotensionlow blood pressure184.7%
Toxicity to various agentspoisoning or toxic effect of one or more substances184.7%
Insomniadifficulty sleeping164.2%
Electrocardiogram QT prolongeda QT prolongation on the ECG153.9%
Overdosea dose above the recommended amount153.9%
Intentional overdosea deliberate overdose133.4%
Dizzinesslight-headedness or unsteadiness123.1%
Product dispensing error123.1%
Anxiety102.6%
Hypertensionhigh blood pressure102.6%
Headachehead pain92.4%
Drug tolerance82.1%
Fatiguetiredness82.1%
Weight decreasedweight loss82.1%
Blood creatine phosphokinase increased71.8%
Blood lactate dehydrogenase increased71.8%
Decreased appetitereduced appetite71.8%
Gastrointestinal disorder71.8%
Myositis71.8%
Rhabdomyolysismuscle breakdown71.8%
Sedationdrowsiness71.8%
Troponin increased71.8%
Condition aggravatedthe condition being treated got worse61.6%
Drug interactionan interaction between medicines61.6%
Nauseafeeling sick61.6%
Sinus bradycardia61.6%
Aggressionaggressive behaviour51.3%
Lethargysluggishness51.3%
Product use in unapproved indicationused for a purpose not on the label51.3%
Transcription medication error51.3%
Vomitingbeing sick51.3%

Download all 35 terms of Guanfacine hydrochloride (CSV)

The counts add to more than 381 reports, because one report can record more than one term. FDA says:

No individual drug is connected to any individual reaction. When a report lists multiple drugs and multiple reactions, there is no way to conclude from the data therein that a given drug is responsible for a given reaction.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

The CSV file has the same rows and the same limits. Its last row is a note that says so.

MedDRA term

The person who codes a report selects the preferred term that agrees best with the description of the reporter. The words under a term are the plain meaning that this site gives.

Not the label

The FDA-approved label of a product lists its adverse reactions. See the official pages at the end of this page.

Same ingredient, other names

Reporters write a brand name or a generic name. Each name has its own page and its own count.

Names of Guanfacine with a page, in the order generic names, brand names, names as reported
NameName typeReports
GuanfacineGeneric name1,445
Guanfacine hydrochloride (this page)Generic name381
IntunivBrand name2,180

Sum of the separately reported names: 4,006. A report that names two of these names is in the sum two times. The sum is not the number of reports for the ingredient.

FDA says:

Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

Importantly, the AEMS data by themselves are not an indicator of the safety profile of the drug or biologic.

Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of . The site read the page on .

Outcomes by year

The table gives the outcomes that the reporters gave, in the terms of FDA.

Outcomes in the reports that name Guanfacine hydrochloride, by the year of the openFDA file that holds the report

The table continues to the right.

Year of the openFDA fileReportsSeriousDeathLife-threateningHospitalization (initial or prolonged)Disability or Permanent DamageCongenital Anomaly/Birth DefectOther Serious (Important Medical Events)Not serious
2004420000022
2005430000031
2007210000011
2008885000030
2009870030041
20101170111054
20111060010054
2012440030020
2013310010002
2014760150031
201518601100512
20162010001001010
201717100241077
201811111240090
2019740040043
20202113001270108
20213216108201216
202245330517102312
202346253015001721
202448380018103110
202531200212001511
20262418021100136

An outcome in a report is not proof that the drug was the cause. The reporter gives the outcome, and FDA does not verify it. FDA says:

The information in these reports has not been scientifically or otherwise verified as to a cause and effect relationship and cannot be used to estimate the incidence of these events.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

The six headings with the names of FDA are the outcome terms of FDA. A report can have more than one outcome. The columns Serious and Not serious are the two values of the openFDA field serious. For the value serious, openFDA gives this description:

The adverse event resulted in death, a life threatening condition, hospitalization, disability, congenital anomaly, or other serious condition

Source: openFDA, Drug adverse event fields (YAML reference). The site read the page on .

The year is the year of the openFDA file that holds the latest version of the report. It is not always the year in which FDA first received the report. The chart of the next section uses the year of first receipt. The latest year is not complete.

Reports by year and month

Reports that name Guanfacine hydrochloride, by the year in which FDA received them
02550200420092013201720212025

The column of 2026 has an outline, because the year is not complete. It has the reports that FDA received through June 2026 only.

Show the figures of the chart as a table
Reports that name Guanfacine hydrochloride, by the year in which FDA received them
YearReports
20044
20054
20072
20088
20098
20109
201112
20124
20134
20147
201519
201619
201717
201812
20199
202026
202132
202245
202346
202444
202527
202623
Reports that name Guanfacine hydrochloride, by month, five years to June 2026
051020222023202420252026

FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

Why a count moves

A count moves for many reasons. The guide gives FDA's words about them.

Patients and reporters

Age of the patient in the reports that name Guanfacine hydrochloride
AgeReportsShareShare as a bar
Under 200%
2 to 119123.9%
12 to 177018.4%
18 to 444511.8%
45 to 64143.7%
65 to 7430.8%
75 and over10.3%
Age not given15741.2%
Sex of the patient in the reports that name Guanfacine hydrochloride
SexReportsShareShare as a bar
Female9725.5%
Male18348%
Unknown or not given10126.5%
Type of reporter in the reports that name Guanfacine hydrochloride
ReporterReportsShareShare as a bar
Physician8722.8%
Pharmacist4511.8%
Other health professional8622.6%
Lawyer00%
Consumer or non-health professional12833.6%
Not given359.2%

Age and sex are as the report gives them. The reporter is the primary source in the report. 66.9% of the reports give the United States as the country.

Reason for use

Reason for use (indication) that the reports of Guanfacine hydrochloride record
Indication as recorded (MedDRA)ReportsShare
Attention deficit hyperactivity disorder9926%
Anxiety20.5%
Hypertension20.5%
Impulsive behaviour20.5%
Tic20.5%

The reporter fills in the indication, and the field is often empty. Each share is of all 381 reports.

Pages near this one

These links are for navigation. No count selected them. The class page lists each drug of the class.

Official pages

The site checked these addresses on . The links open in a new tab.

Cite this page

Reported Reactions. Guanfacine hydrochloride: adverse event reports that FDA received. https://reportedreactions.com/drug/guanfacine-hydrochloride/ Source: U.S. Food and Drug Administration, openFDA Drug Adverse Event (FAERS) files, release of . Reports received through .

Where the data come from

The counts come from the openFDA Drug Adverse Event (FAERS) bulk files, release of 1 Oct 2026. The files have the reports that FDA received through 30 Jun 2026. A drug name is the name on the report. The site matches it to a brand name or a generic name of the National Drug Code Directory of 2 Oct 2026. A class is the pharmacologic class (EPC) of the FDA label.

A report is in the count when it names Guanfacine hydrochloride as a suspect or interacting product. The 758 reports that name it only as a concomitant medicine are not in the count. The site does not publish a report narrative, a lot number, a detail of a patient or the identity of a reporter. The record of FDA is the authority. See how the site counts reports, the data sources and the corrections page.

Questions

Do these reports show that Guanfacine hydrochloride was responsible for the reactions?

No. FDA says:

For any given report, there is no certainty that a suspected drug caused the event.

Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of . The site read the page on .

A reaction can relate to the condition that the drug treats, to other medicines, or to something else.

Is this the list of reactions on the label of Guanfacine hydrochloride?

No. It is a count of what people reported to FDA: 381 reports from April 2004 to June 2026. The FDA-approved label of a product lists its adverse reactions. The official pages at the end of this page link to the labels.

Who sent these reports?

Consumer or non-health professional (33.6%), physician (22.8%) and other health professional (22.6%). These are the types of reporter for the reports that name this drug.

If a manufacturer receives an adverse event report, it is normally required to send the report to FDA.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

How does a person report an adverse event?

FDA runs MedWatch, a program that takes voluntary reports from health professionals, patients and consumers. The guide on how to report has the links.