Haemophagocytic lymphohistiocytosis adverse event reports that record this term

Kind of term: MedDRA preferred term

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.

Reports on file

From May 2008 to June 2026, FDA received 7,130 adverse event reports that record the MedDRA preferred term Haemophagocytic lymphohistiocytosis. The person who codes a report selects the term that agrees best with the description of the reporter.

FDA received 1,119 reports in the 12 months to June 2026 and 1,127 in the 12 months before. FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

By reports in the 12 months to June 2026, this term was number 565 of 1,436 reaction terms with a page. Of the 1,332,454 drug reports that FDA received in the 12 months to June 2026, 1,119 (0.1%) record this term. Reports for female patients were 42.1% of the reports that record this term 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.

MedDRA

The Medical Dictionary for Regulatory Activities. The person who codes a report selects the preferred term that agrees best with the description of the reporter. FDA does not publish the description.

Data version

openFDA FAERS release of 29 Oct 2026. Reports received through 30 Jun 2026.

Drugs in these reports

The table has the 134 drug pages with 25 or more reports that record this term. The rows are in order of name. A drug page with fewer reports for this term is not in the table. The counts are the counts that the site keeps for each reaction term, and a count can be lower than the count of FDA.

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.

Drugs that the reports with the term Haemophagocytic lymphohistiocytosis name as a suspect product, in order of name
Drug	Class	Reports with this term
Abatacept	Selective T cell costimulation modulator	34
Acetaminophen		29
Actemra	Interleukin-6 receptor antagonist	105
Acyclovir	Herpes simplex virus nucleoside analog DNA polymerase inhibitor	37
Adalimumab	Tumor necrosis factor blocker	219
Alemtuzumab	CD52-directed cytolytic antibody	79
Allopurinol	Xanthine oxidase inhibitor	66
Amphotericin b	Lipid-based polyene antifungal	38
Anakinra	Interleukin-1 receptor antagonist	352
Asparaginase		27
Atezolizumab	Programmed death Receptor-1 blocking antibody	50
Avastin	Vascular endothelial growth factor inhibitor	47
Axicabtagene ciloleucel	CD19-directed chimeric antigen receptor	39
Azacitidine	Nucleoside metabolic inhibitor	45
Azathioprine	Purine antimetabolite	193
Bactrim	Dihydrofolate reductase inhibitor antibacterial	50
Baricitinib	Janus kinase inhibitor	48
Basiliximab	Interleukin-2 receptor blocking antibody	71
Belatacept	Selective T cell costimulation blocker	35
Bevacizumab	Vascular endothelial growth factor inhibitor	38
Bortezomib	Proteasome inhibitor	35
Busulfan	Alkylating drug	79
Busulfex		37
Canakinumab		98
Carbamazepine	Mood stabilizer	33
Carboplatin	Platinum-based drug	229
Carvykti		86
Caspofungin		29
Cefotaxime	Cephalosporin antibacterial	25
Ceftriaxone	Cephalosporin antibacterial	32
CellCept	Antimetabolite immunosuppressant	44
Ciclosporin		55
Ciltacabtagene autoleucel		28
Cisplatin	Platinum-based drug	70
Clobazam	Benzodiazepine	34
Cotrimoxazole		29
Cyclophosphamide	Alkylating drug	571
Cyclosporine	Calcineurin inhibitor immunosuppressant	420
Cytarabine	Nucleoside metabolic inhibitor	171
Dabrafenib	Kinase inhibitor	33
Daunorubicin		45
Dexamethasone	Corticosteroid	531
Doxorubicin	Anthracycline topoisomerase inhibitor	165
Doxorubicin hydrochloride	Anthracycline topoisomerase inhibitor	71
Emapalumab		46
Etanercept	Tumor necrosis factor blocker	74
Etoposide	Topoisomerase inhibitor	451
Everolimus	Kinase inhibitor	42
Filgrastim	Leukocyte growth factor	60
Fluconazole	Azole antifungal	51
Fludarabine	Nucleoside metabolic inhibitor	235
Fludarabine phosphate	Nucleoside metabolic inhibitor	69
Ganciclovir	Cytomegalovirus nucleoside analog DNA polymerase inhibitor	69
Gemcitabine	Nucleoside metabolic inhibitor	29
Human immunoglobulin g	Human immunoglobulin G	83
Humira		32
Hydrocortisone	Corticosteroid	27
Hydroxychloroquine	Antimalarial	100
Ibuprofen	Nonsteroidal anti-inflammatory drug	49
Idarubicin		25
Ifosfamide	Alkylating drug	31
Ilaris		131
Imbruvica	Kinase inhibitor	29
Immune globulin (human)	Human immunoglobulin G	29
Infliximab	Tumor necrosis factor blocker	193
Ipilimumab	CTLA-4-directed blocking antibody	75
Isoniazid	Antimycobacterial	38
Jakafi	Janus kinase inhibitor	47
Keytruda	Programmed death Receptor-1 blocking antibody	230
Kineret	Interleukin-1 receptor antagonist	140
Kymriah	CD19-directed chimeric antigen receptor	91
Lamictal	Anti-epileptic agent	52
Lamivudine	Hepatitis B virus nucleoside analog reverse transcriptase inhibitor	30
Lamotrigine	Anti-epileptic agent	316
Lapine t-lymphocyte immune globulin		26
Leflunomide	Antirheumatic agent	48
Lenalidomide	Thalidomide analog	54
Lenvima	Kinase inhibitor	25
Levetiracetam		82
Levofloxacin	Fluoroquinolone antibacterial	35
Linezolid	Oxazolidinone antibacterial	28
Mekinist	Kinase inhibitor	39
Melphalan	Alkylating drug	115
Mercaptopurine	Nucleoside metabolic inhibitor	57
Meropenem	Penem antibacterial	56
Methotrexate	Folate analog metabolic inhibitor	554
Methotrexate sodium	Folate analog metabolic inhibitor	68
Methylprednisolone	Corticosteroid	486
Methylprednisolone sodium succinate	Corticosteroid	34
Metronidazole	Nitroimidazole antimicrobial	52
Midazolam	Benzodiazepine	34
Moxifloxacin	Fluoroquinolone antibacterial	35
Mycophenolate mofetil	Antimetabolite immunosuppressant	536
Mycophenolic acid	Antimetabolite immunosuppressant	168
Nivolumab	Programmed death Receptor-1 blocking antibody	116
Opdivo	Programmed death Receptor-1 blocking antibody	142
Oxaliplatin	Platinum-based drug	31
Paclitaxel	Microtubule inhibitor	121
Pembrolizumab	Programmed death Receptor-1 blocking antibody	172
Pemetrexed	Folate analog metabolic inhibitor	81
Phenytoin	Anti-epileptic agent	67
Piperacillin and tazobactam	Penicillin-class antibacterial	43
Piperacillin sodium,tazobactam sodium		52
Prednisolone	Corticosteroid	442
Prednisone	Corticosteroid	743
Prograf	Calcineurin inhibitor immunosuppressant	25
Quetiapine	Atypical antipsychotic	27
Remicade	Tumor necrosis factor blocker	37
Rifampin	Rifamycin antibacterial	43
Rituximab	CD20-directed cytolytic antibody	424
Ruxolitinib	Janus kinase inhibitor	123
Sulfamethoxazole, trimethoprim	Dihydrofolate reductase inhibitor antibacterial	93
Sulfasalazine	Aminosalicylate	38
Tacrolimus	Calcineurin inhibitor immunosuppressant	651
Tafinlar	Kinase inhibitor	39
Tecartus		30
Tecentriq	Programmed death Receptor-1 blocking antibody	74
Thalidomide		33
Thiotepa	Alkylating drug	53
Thymocyte Immune Globulin		46
Thymoglobulin	Immunoglobulin G	48
Tisagenlecleucel	CD19-directed chimeric antigen receptor	28
Tocilizumab	Interleukin-6 receptor antagonist	278
Tofacitinib	Janus kinase inhibitor	65
Trametinib	Kinase inhibitor	41
Trastuzumab	HER2/neu receptor antagonist	25
Treosulfan		30
Valganciclovir	Cytomegalovirus nucleoside analog DNA polymerase inhibitor	50
Vancomycin	Glycopeptide antibacterial	92
Venetoclax	BCL-2 inhibitor	63
Vincristine		148
Vincristine sulfate	Vinca alkaloid	52
Yervoy	CTLA-4-directed blocking antibody	94
Yescarta	CD19-directed chimeric antigen receptor	100

The page of each drug has the count of each reaction term in its reaction lookup.

Drug classes in these reports

The table has the 48 pharmacologic classes with 50 or more reports that record this term. The rows are in order of name.

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.

Pharmacologic classes of the drugs that the reports with the term Haemophagocytic lymphohistiocytosis name, in order of name
Class	Reports with this term
Alkylating drug	896
Anthracycline topoisomerase inhibitor	250
Anti-epileptic agent	485
Antimalarial	132
Antimetabolite immunosuppressant	748
Antimycobacterial	63
Antirheumatic agent	54
Atypical antipsychotic	51
Azole antifungal	104
BCL-2 inhibitor	83
Benzodiazepine	74
Calcineurin inhibitor immunosuppressant	1,130
CD19-directed chimeric antigen receptor	258
CD20-directed cytolytic antibody	452
CD52-directed cytolytic antibody	95
Cephalosporin antibacterial	89
Corticosteroid	2,325
CTLA-4-directed blocking antibody	181
Cytomegalovirus nucleoside analog DNA polymerase inhibitor	121
Dihydrofolate reductase inhibitor antibacterial	158
Fluoroquinolone antibacterial	83
Folate analog metabolic inhibitor	722
Glycopeptide antibacterial	98
Herpes simplex virus nucleoside analog DNA polymerase inhibitor	51
Human immunoglobulin G	117
Immunoglobulin G	67
Interleukin-1 receptor antagonist	492
Interleukin-2 receptor blocking antibody	71
Interleukin-6 receptor antagonist	385
Janus kinase inhibitor	356
Kinase inhibitor	372
Leukocyte growth factor	64
Microtubule inhibitor	147
Nitroimidazole antimicrobial	52
Nonsteroidal anti-inflammatory drug	78
Nucleoside metabolic inhibitor	644
Penem antibacterial	56
Penicillin-class antibacterial	76
Platinum-based drug	330
Programmed death Receptor-1 blocking antibody	784
Proteasome inhibitor	83
Purine antimetabolite	214
Thalidomide analog	74
Topoisomerase inhibitor	472
Tumor necrosis factor blocker	535
Vascular endothelial growth factor inhibitor	85
Vinca alkaloid	60
Xanthine oxidase inhibitor	69

A class with many reports in all has many reports for almost every term.

Reports by month

Reports that record Haemophagocytic lymphohistiocytosis, 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.

Patients in these reports

Age of the patient in the reports that record Haemophagocytic lymphohistiocytosis
Age	Reports	Share
Under 2	159	2.2%
2 to 11	632	8.9%
12 to 17	356	5%
18 to 44	1,558	21.9%
45 to 64	1,643	23%
65 to 74	1,016	14.2%
75 and over	405	5.7%
Age not given	1,361	19.1%

Sex of the patient in the reports that record Haemophagocytic lymphohistiocytosis
Sex	Reports	Share
Female	3,001	42.1%
Male	3,169	44.4%
Unknown or not given	960	13.5%

Age and sex are as the report gives them. 29.5% of these reports give the United States as the country.

Terms near this one

These are the next terms in the A to Z list. The links are for navigation.

Official pages

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. Haemophagocytic lymphohistiocytosis: adverse event reports that record this term. https://reportedreactions.com/reaction/haemophagocytic-lymphohistiocytosis/ 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.

The count has the reports with each spelling of one MedDRA preferred term. 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

What does Haemophagocytic lymphohistiocytosis mean in an adverse event report?

It is a MedDRA preferred term. FDA codes the description of a reporter with the MedDRA dictionary. The openFDA files do not have the description itself, and this site does not show it.

Does a drug in the table mean that the drug was responsible for this reaction?

No. FDA says:

No individual drug is connected to any individual reaction.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

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.

What does this page tell a person who has this symptom?

This page gives counts of reports. It cannot assess a person. A pharmacist or a clinician can assess a person.

If this is a medical emergency, please call 911.
Source: FDA, MedWatch Online Voluntary Reporting Form. The site read the page on 2 Oct 2026.

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