Cycloserine adverse event reports that FDA received

Name: Reaction terms in FDA adverse event reports that name Cycloserine
Creator: Reported Reactions
License: https://creativecommons.org/publicdomain/zero/1.0/

Name type: Generic name

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 2 Oct 2026. The data have the reports that FDA received through 30 Jun 2026.

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 2 Oct 2026.

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 2 Oct 2026.

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

Drug reports received through 30 Jun 2026. Device reports have a separate cutoff, 30 Sep 2026. Why a report count is not a rate.

Reports on file

From October 2004 to June 2026, FDA received 1,557 adverse event reports that name Cycloserine. In these reports the drug is a suspect or interacting product.

In the same period, 712 further reports name it only as a concomitant medicine. The counts on this page do not include these reports.

FDA received 113 reports in the 12 months to June 2026 and 81 in the 12 months before. FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

Of the 1,332,454 drug reports that FDA received in the 12 months to June 2026, 113 (under 0.1%) name Cycloserine. Reports from consumers or other non-health professionals were 8.3% of the reports that name Cycloserine and 45.8% of all drug reports.

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 11 Mar 2026. The site read the page on 2 Oct 2026.

Suspect product

FDA records each drug in a report as suspect, concomitant or interacting. This page counts the reports in which Cycloserine 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 2 Oct 2026.

Data version

openFDA FAERS release of 29 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 2 Oct 2026.

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 11 Mar 2026. The site read the page on 2 Oct 2026.

The latest update of the FDA data, recorded on 28 Oct 2026, changed no count of this page.

In April to June 2026, FDA received 24 reports that name Cycloserine.
In January to March 2026, FDA received 48.
In April to June 2025, FDA received 11.

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 updates Feed 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 181 reaction terms that 5 or more reports record. A term with fewer than 5 reports is not in the table.

The site keeps reaction terms for 1,539 of the 1,557 reports (98.8%).

The reports of the other years are not in the counts.

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

Find a reaction term

The table shows the first 50 of 181 terms.

Reaction terms in the reports that name Cycloserine, most reports first
Reaction term (MedDRA) and plain meaning	Reports	Share of the 1,557 reports
Electrocardiogram QT prolongeda QT prolongation on the ECG	236	15.2%
Off label useused for a purpose or in a way not on the label	184	11.8%
Anaemialow red blood cells	157	10.1%
Vomitingbeing sick	145	9.3%
Neuropathy peripheralnerve damage in hands or feet	144	9.2%
Nauseafeeling sick	117	7.5%
Hepatotoxicityliver injury	92	5.9%
Deaththe patient died; cause not stated by this term	79	5.1%
Drug resistance	76	4.9%
Tuberculosis	76	4.9%
Dyspnoeashortness of breath	71	4.6%
Astheniaweakness or lack of energy	64	4.1%
Intentional product use issuedeliberate use not as intended	61	3.9%
Drug reaction with eosinophilia and systemic symptomsDRESS, a severe reaction with rash, fever and organ involvement	55	3.5%
Treatment failurethe treatment did not work	54	3.5%
Arthralgiajoint pain	53	3.4%
Hypokalaemialow blood potassium	52	3.3%
Product use in unapproved indicationused for a purpose not on the label	52	3.3%
Gastrointestinal disorder	50	3.2%
Decreased appetitereduced appetite	44	2.8%
Drug-induced liver injury	44	2.8%
Respiratory failurethe lungs could not supply enough oxygen	44	2.8%
Diarrhoealoose or frequent stools	43	2.8%
Pyrexiafever	43	2.8%
Aspartate aminotransferase increasedraised liver enzyme (AST)	40	2.6%
Dizzinesslight-headedness or unsteadiness	40	2.6%
Psychotic disordera loss of contact with reality	38	2.4%
Drug ineffectivethe medicine did not work as expected	36	2.3%
Headachehead pain	36	2.3%
Rashskin rash	34	2.2%
Alanine aminotransferase increasedraised liver enzyme (ALT)	33	2.1%
Haemoglobin decreasedlow haemoglobin	33	2.1%
Seizurea fit or convulsion	33	2.1%
Thrombocytopenialow platelets	32	2.1%
Insomniadifficulty sleeping	31	2%
Depressionlow mood	29	1.9%
Tinnitusringing in the ears	29	1.9%
Acute kidney injurysudden loss of kidney function	28	1.8%
Optic neuritis	27	1.7%
Cough	26	1.7%
Hypothyroidismunderactive thyroid	26	1.7%
Product use issuea problem in how the product was used	25	1.6%
Condition aggravatedthe condition being treated got worse	23	1.5%
Pulmonary tuberculosis	23	1.5%
Exposure during pregnancythe medicine was taken during pregnancy	22	1.4%
Platelet count decreasedlow platelet count	22	1.4%
Treatment noncompliancethe treatment was not taken as directed	21	1.3%
Anxiety	20	1.3%
Arrhythmia	20	1.3%
Hepatic enzyme increasedraised liver enzymes	20	1.3%

Download all 181 terms of Cycloserine (CSV)

The counts add to more than 1,557 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 2 Oct 2026.

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.

Outcomes by year

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

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

The table continues to the right.

Year of the openFDA file	Reports	Serious	Death	Life-threatening	Hospitalization (initial or prolonged)	Disability or Permanent Damage	Congenital Anomaly/Birth Defect	Other Serious (Important Medical Events)	Not serious
2005	2	2	0	0	0	0	0	2	0
2006	1	1	1	0	1	0	0	0	0
2007	4	4	1	1	4	1	0	1	0
2008	2	2	0	0	2	2	0	1	0
2009	3	3	1	0	1	1	1	0	0
2010	1	1	0	0	0	0	0	1	0
2011	14	13	0	0	5	0	0	10	1
2012	5	5	0	0	1	0	0	4	0
2013	13	13	4	1	8	0	0	4	0
2014	28	28	4	9	11	1	0	16	0
2015	34	34	13	0	11	1	0	24	0
2016	69	68	19	12	26	0	0	39	1
2017	94	93	25	9	35	1	0	59	1
2018	240	239	75	21	109	14	0	150	1
2019	261	259	71	25	106	11	0	191	2
2020	204	201	39	15	75	2	0	157	3
2021	88	88	19	6	27	2	0	64	0
2022	167	165	24	21	47	2	0	133	2
2023	71	71	10	5	33	10	0	48	0
2024	88	88	9	9	30	2	0	74	0
2025	88	87	12	9	34	1	1	68	1
2026	80	79	32	5	8	0	1	61	1

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 2 Oct 2026.

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 2 Oct 2026.

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 Cycloserine, by the year in which FDA received them

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 Cycloserine, by the year in which FDA received them
Year	Reports
2004	1
2005	2
2006	1
2007	4
2008	2
2009	3
2010	1
2011	15
2012	5
2013	13
2014	29
2015	38
2016	90
2017	116
2018	287
2019	290
2020	164
2021	86
2022	107
2023	64
2024	87
2025	80
2026	72

Reports that name Cycloserine, by month, five years to June 2026

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 Cycloserine
Age	Reports	Share
Under 2	15	1%
2 to 11	37	2.4%
12 to 17	46	3%
18 to 44	711	45.7%
45 to 64	391	25.1%
65 to 74	78	5%
75 and over	30	1.9%
Age not given	249	16%

Sex of the patient in the reports that name Cycloserine
Sex	Reports	Share
Female	604	38.8%
Male	772	49.6%
Unknown or not given	181	11.6%

Type of reporter in the reports that name Cycloserine
Reporter	Reports	Share
Physician	793	50.9%
Pharmacist	14	0.9%
Other health professional	609	39.1%
Lawyer	0	0%
Consumer or non-health professional	129	8.3%
Not given	12	0.8%

Age and sex are as the report gives them. The reporter is the primary source in the report. 7.1% of the reports give the United States as the country.

Reason for use

Reason for use (indication) that the reports of Cycloserine record
Indication as recorded (MedDRA)	Reports	Share
Tuberculosis	1,053	67.6%
Pulmonary tuberculosis	264	17%
Lymph node tuberculosis	8	0.5%
Meningitis tuberculous	7	0.4%
Mycobacterial infection	6	0.4%
Tuberculosis of central nervous system	5	0.3%

The reporter fills in the indication, and the field is often empty. Each share is of all 1,557 reports.

Drugs in the same reports

Other drugs that the reports of Cycloserine name, in any role, in order of name
Drug	Reports that name the two
Amikacin	272
Bedaquiline	662
Clofazimine	951
Ethambutol	329
Levofloxacin	585
Linezolid	1,088
Moxifloxacin	421
Pyrazinamide	637
Pyridoxine	208
Sirturo	374

The table has the 10 drug names that these reports name most. Two names in one report says only that the report recorded the two. It says nothing about the part of a product in the event.

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 2 Oct 2026.

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 11 Mar 2026. The site read the page on 2 Oct 2026.

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These links are for navigation. No count selected them.

Official pages

DailyMed labels for CycloserineThe labels (prescribing information) that have this name, at the National Library of Medicine.
MedWatch Online Voluntary Reporting FormThe online form of FDA for a voluntary report.
MedWatch: The FDA Safety Information and Adverse Event Reporting ProgramThe page of the FDA program that receives reports about drugs and devices.
FDA Adverse Event Monitoring System (AEMS) Public DashboardThe public dashboard of FDA for adverse event reports on drugs and biologics.

The site checked these addresses on 2 Oct 2026. The links open in a new tab.

Cite this page

Reported Reactions. Cycloserine: adverse event reports that FDA received. https://reportedreactions.com/drug/cycloserine/ Source: U.S. Food and Drug Administration, openFDA Drug Adverse Event (FAERS) files, release of 29 Oct 2026. Reports received through 30 Jun 2026.

Where the data come from

The counts come from the openFDA Drug Adverse Event (FAERS) bulk files, release of 29 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 Nov 2026. A class is the pharmacologic class (EPC) of the FDA label.

A report is in the count when it names Cycloserine as a suspect or interacting product. The 712 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 Cycloserine 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 11 Mar 2026. The site read the page on 2 Oct 2026.

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 Cycloserine?

No. It is a count of what people reported to FDA: 1,557 reports from October 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?

Physician (50.9%), other health professional (39.1%) and consumer or non-health professional (8.3%). 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 2 Oct 2026.

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.

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