MedDRA preferred term

Blood count abnormal: adverse event reports recording this term

15,173 reports to FDA record it, 2004–2021; 0.1% of the database.

Read first · FDA's statement on these data

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. openFDA, FDA

FDA adds: "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 "cannot be used to estimate the incidence of these events."

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.

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

15,173
reports recording the term: 0.1% of all reports; 0
reports, 12 months to June 2026: 0 in the 12 months before; 71.3%
marked serious by the reporter: 57.4% across all reports; 4.6%
record death among outcomes, as reported: 9.1% across all reports

"Blood count abnormal" is a MedDRA preferred term recorded in 15,173 adverse event reports received by FDA, 0.1% of the database, from November 2004 to September 2021. The term is chosen by whoever codes the report to match what the reporter described.

0 reports recorded it in the 12 months to June 2026, and none in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Of reports recording this term, 71.3% are marked serious, 4.6% include death among the outcomes and 38.4% include hospitalisation, as reported.

The drugs listed most often as suspect products in those reports are Prednisone, Tiotropium bromide and Salbutamol sulfate. That order mostly follows how many reports each drug has overall; the table also gives the term's share within each drug's own reports. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

Drugs listed as suspect products in these reports

Drug	Class	Reports with this term	Share of the drug's own reports
Prednisone	Corticosteroid	1,568	0.9%
Tiotropium bromide	Anticholinergic	1,383	1.8%
Salbutamol sulfate	—	1,230	31.6%
Salbutamol	—	1,227	15.2%
Ibrance	Kinase inhibitor	1,142	1.4%
Jakafi	Janus kinase inhibitor	1,135	2%
Symbicort	Corticosteroid	1,035	2.6%
Singulair	Leukotriene receptor antagonist	1,004	5.3%
Revlimid	Thalidomide analog	972	0.3%
Nucala	Interleukin-5 antagonist	768	2.5%
Advair Hfa	Corticosteroid	617	3.1%
Ipratropium bromide	Anticholinergic	536	6.5%
Breo Ellipta	Corticosteroid	512	2.3%
Alvesco	—	493	11.2%
Albuterol sulfate	beta2-Adrenergic agonist	487	1.1%
Salbutamol sulphate	—	402	20.4%
Imbruvica	Kinase inhibitor	394	0.6%
Mepolizumab	Interleukin-5 antagonist	388	2.4%
Zenhale	—	368	15.4%
Budesonide Formoterol Fumarate	—	367	9.4%
Zejula	Poly(ADP-Ribose) polymerase inhibitor	356	2.3%
Montelukast	Leukotriene receptor antagonist	312	2.4%
Humira	—	287	0%
Venclexta	BCL-2 inhibitor	284	0.8%
Pegasys	Interferon alpha	274	0.7%

Drugs with a page on this site, ordered by the number of their reports recording this term. The last column is the term's share within that drug's own reports, against 0.1% across the whole database. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

By pharmacologic class

Class	Reports with this term	Share of class reports	Median drug in class
Corticosteroid	4,720	0.6%	0%
Kinase inhibitor	2,234	0.3%	0%
Anticholinergic	2,223	1.4%	0%
Leukotriene receptor antagonist	1,425	3.7%	2.4%
Janus kinase inhibitor	1,247	0.4%	0%
Thalidomide analog	1,165	0.2%	0.1%
Interleukin-5 antagonist	1,156	2.4%	2.4%
Poly(ADP-Ribose) polymerase inhibitor	672	1.3%	0.6%
beta2-Adrenergic agonist	572	0.6%	0.2%
Endothelin receptor antagonist	419	0.2%	0.3%

Classes ordered by count. Class shares follow the class's overall report volume as much as anything else.

Patients in these reports

Patient age

Under 20.1%10

2 to 110.3%49

12 to 170.4%63

18 to 446.6%1,005

45 to 6422.4%3,403

65 to 7416.4%2,494

75 and over12.4%1,885

Age not given41.3%6,264

Patient sex

Female56.7%8,609

Male33.3%5,059

Not given9.9%1,505

Grey bar: all 20,646,523 reports in the database. 68% of these reports give the United States as the country.

Questions about "Blood count abnormal"

What does "Blood count abnormal" mean in an adverse event report?

It is a MedDRA preferred term, the dictionary FDA uses to code what a reporter described. The report's own description is not published by openFDA and is not shown here.

How many reports record blood count abnormal?

15,173 reports through June 2026 (0.1% of all reports), 0 of them in the latest 12 months.

Which drugs appear most often in these reports?

Prednisone (1,568), Tiotropium bromide (1,383), Salbutamol sulfate (1,230), Salbutamol (1,227) and Ibrance (1,142). Drugs with many reports overall lead almost every term's list. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Does a drug appearing here mean it was responsible for this reaction?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

I have this symptom. What should I do?

This site cannot assess anyone. A pharmacist or clinician can; for an emergency, call the local emergency number. Nothing on this page is medical advice.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. Terms are pooled across spelling and capitalisation variants of one MedDRA preferred term. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.