Tykerb (lapatinib) adverse event reports that FDA received

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

Name type: Brand name
Generic name: Lapatinib
Class: Kinase inhibitor

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 April 2007 to May 2026, FDA received 9,860 adverse event reports that name Tykerb. In these reports the drug is a suspect or interacting product.

In the same period, 514 further reports name it only as a concomitant medicine. The counts on this page do not include these reports.

FDA received 23 reports in the 12 months to June 2026 and 94 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, 23 (under 0.1%) name Tykerb. Reports for female patients were 91.9% of the reports that name Tykerb and 52.7% 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 Tykerb 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 1 report that names Tykerb.
In January to March 2026, FDA received 9.
In April to June 2025, FDA received 10.

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 447 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 all 9,860 reports.

The site keeps a term for a year only if two or more reports of that year record it.

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 447 terms.

Reaction terms in the reports that name Tykerb, most reports first
Reaction term (MedDRA) and plain meaning	Reports	Share of the 9,860 reports
Diarrhoealoose or frequent stools	3,164	32.1%
Deaththe patient died; cause not stated by this term	1,240	12.6%
Nauseafeeling sick	1,179	12%
Fatiguetiredness	988	10%
Rashskin rash	832	8.4%
Vomitingbeing sick	779	7.9%
Palmar-plantar erythrodysaesthesia syndrome	564	5.7%
Decreased appetitereduced appetite	393	4%
Drug ineffectivethe medicine did not work as expected	390	4%
Disease progressionthe disease advanced	365	3.7%
Dry skin	348	3.5%
Astheniaweakness or lack of energy	301	3.1%
Malignant neoplasm progression	285	2.9%
Pruritusitching	285	2.9%
Weight decreasedweight loss	279	2.8%
Stomatitissore mouth	272	2.8%
Dyspnoeashortness of breath	261	2.6%
Malaisegeneral feeling of being unwell	259	2.6%
Erythemaskin redness	255	2.6%
Dehydration	246	2.5%
Pain in extremitypain in an arm or leg	239	2.4%
Dizzinesslight-headedness or unsteadiness	237	2.4%
Metastases to central nervous system	224	2.3%
Breast cancer metastatic	223	2.3%
Breast cancer	200	2%
Painpain, site not specified	194	2%
Headachehead pain	183	1.9%
Constipation	176	1.8%
Pyrexiafever	166	1.7%
Abdominal pain upperupper stomach pain	154	1.6%
Cough	149	1.5%
Dyspepsiaindigestion	144	1.5%
Back pain	138	1.4%
Off label useused for a purpose or in a way not on the label	135	1.4%
Abdominal painstomach or belly pain	130	1.3%
Skin discolourationa change in skin colour	129	1.3%
Epistaxisnosebleed	127	1.3%
Skin fissures	127	1.3%
Hypoaesthesianumbness	126	1.3%
Skin exfoliationpeeling skin	122	1.2%
Paronychia	120	1.2%
Paraesthesiatingling or pins and needles	119	1.2%
Insomniadifficulty sleeping	116	1.2%
Pneumonialung infection	115	1.2%
Acne	114	1.2%
Blistera blister	111	1.1%
Dysphagiadifficulty swallowing	110	1.1%
Adverse drug reactiona harmful or unpleasant reaction (the term names a medicine)	108	1.1%
Oedema peripheralswelling of the legs, ankles or hands	107	1.1%
Muscle spasmsmuscle cramps	105	1.1%

Download all 447 terms of Tykerb (CSV)

The counts add to more than 9,860 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.

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 Lapatinib with a page, in the order generic names, brand names, names as reported
Name	Name type	Reports
Lapatinib	Generic name	4,544
Tykerb (this page)	Brand name	9,860

Sum of the separately reported names: 14,404. 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 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.

Outcomes by year

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

Outcomes in the reports that name Tykerb, 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
2007	767	186	31	2	73	11	0	94	581
2008	345	107	27	6	42	11	1	50	238
2009	743	299	80	14	112	13	0	148	444
2010	1,020	532	139	27	187	20	0	239	488
2011	1,125	686	203	24	220	20	0	302	439
2012	490	419	130	14	149	10	0	157	71
2013	975	556	179	18	169	14	0	255	419
2014	765	401	161	17	144	15	0	196	364
2015	1,030	468	234	8	129	1	1	363	562
2016	371	234	87	12	73	4	0	113	137
2017	476	255	99	9	78	4	0	118	221
2018	440	253	101	7	68	3	0	113	187
2019	442	230	81	4	67	0	1	93	212
2020	313	192	73	3	51	0	0	96	121
2021	165	141	63	7	37	2	0	70	24
2022	80	59	30	4	25	1	0	25	21
2023	68	54	10	2	28	2	0	33	14
2024	136	101	26	5	49	0	0	63	35
2025	91	86	11	4	41	0	0	76	5
2026	18	15	9	2	1	0	0	11	3

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 Tykerb, 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 Tykerb, by the year in which FDA received them
Year	Reports
2007	666
2008	375
2009	658
2010	776
2011	1,179
2012	931
2013	976
2014	802
2015	936
2016	381
2017	476
2018	456
2019	439
2020	327
2021	150
2022	78
2023	66
2024	135
2025	43
2026	10

Reports that name Tykerb, 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 Tykerb
Age	Reports	Share
Under 2	1	under 0.1%
2 to 11	2	under 0.1%
12 to 17	5	0.1%
18 to 44	842	8.5%
45 to 64	3,441	34.9%
65 to 74	1,050	10.6%
75 and over	478	4.8%
Age not given	4,041	41%

Sex of the patient in the reports that name Tykerb
Sex	Reports	Share
Female	9,063	91.9%
Male	301	3.1%
Unknown or not given	496	5%

Type of reporter in the reports that name Tykerb
Reporter	Reports	Share
Physician	1,827	18.5%
Pharmacist	687	7%
Other health professional	888	9%
Lawyer	0	0%
Consumer or non-health professional	6,356	64.5%
Not given	102	1%

Age and sex are as the report gives them. The reporter is the primary source in the report. 73.6% of the reports give the United States as the country.

Reason for use

Reason for use (indication) that the reports of Tykerb record
Indication as recorded (MedDRA)	Reports	Share
Breast cancer	4,164	42.2%
Breast cancer metastatic	797	8.1%
Breast cancer female	504	5.1%
Neoplasm malignant	147	1.5%
Her2 positive breast cancer	122	1.2%
Brain neoplasm malignant	40	0.4%

The reporter fills in the indication, and the field is often empty. Each share is of all 9,860 reports.

Drugs in the same reports

Other drugs that the reports of Tykerb name, in any role, in order of name
Drug	Reports that name the two
Capecitabine	697
Dexamethasone	289
Herceptin	849
Kadcyla	238
Perjeta	187
Trastuzumab	330
Xeloda	2,977
Xgeva	175
Zofran	214
Zometa	258

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.

Pages near this one

Lapatinib same ingredient
Turalio same class
Vandetanib same class
Tukysa same class
Vanflyta same class
Tucatinib same class
Vemurafenib same class
Tygacil next in the A to Z list
Tylenol next in the A to Z list
Tyenne next in the A to Z list
Tylenol 8 HR Arthritis Pain next in the A to Z list
Twynsta next in the A to Z list

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

Official pages

DailyMed labels for TykerbThe 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. Tykerb: adverse event reports that FDA received. https://reportedreactions.com/drug/tykerb/ 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 Tykerb as a suspect or interacting product. The 514 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 Tykerb 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 Tykerb?

No. It is a count of what people reported to FDA: 9,860 reports from April 2007 to May 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 (64.5%), physician (18.5%) and other health professional (9%). 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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