MedDRA preferred term

Full blood count abnormal: adverse event reports recording this term

10,400 reports to FDA record it, 2004–2026; 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.

10,400
reports recording the term: 0.1% of all reports; 802
reports, 12 months to June 2026: 933 in the 12 months before; 75.1%
marked serious by the reporter: 57.4% across all reports; 4.8%
record death among outcomes, as reported: 9.1% across all reports

"Full blood count abnormal" is a MedDRA preferred term recorded in 10,400 adverse event reports received by FDA, 0.1% of the database, from January 2004 to June 2026. The term is chosen by whoever codes the report to match what the reporter described.

802 reports recorded it in the 12 months to June 2026, down 14% from 933 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, 75.1% are marked serious, 4.8% include death among the outcomes and 38.5% include hospitalisation, as reported.

The drugs listed most often as suspect products in those reports are Prednisone, Albuterol and Albuterol 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	2,346	1.3%
Albuterol	beta2-Adrenergic agonist	1,965	11%
Albuterol sulfate	beta2-Adrenergic agonist	1,872	4.2%
Tiotropium bromide	Anticholinergic	1,555	2%
Nucala	Interleukin-5 antagonist	1,204	3.9%
Singulair	Leukotriene receptor antagonist	1,182	6.2%
Symbicort	Corticosteroid	1,157	3%
Ibrance	Kinase inhibitor	1,071	1.3%
Budesonide	Corticosteroid	1,045	7.1%
Budesonide Formoterol Fumarate	—	990	25.4%
Pulmicort Turbuhaler	—	647	14.6%
Advair Hfa	Corticosteroid	580	3%
Alvesco	—	577	13.2%
Revlimid	Thalidomide analog	572	0.2%
Mepolizumab	Interleukin-5 antagonist	549	3.4%
Omalizumab	Anti-IgE	547	5.2%
Zenhale	—	541	22.7%
Pantoprazole	Proton pump inhibitor	535	1.2%
Breo Ellipta	Corticosteroid	521	2.3%
Azithromycin	Macrolide antimicrobial	503	2.9%
Ergocalciferol	Provitamin D2 compound	501	5%
Aspirin	Nonsteroidal anti-inflammatory drug	460	0.6%
Ipratropium bromide	Anticholinergic	454	5.5%
Montelukast sodium	Leukotriene receptor antagonist	448	6.7%
Umeclidinium bromide	—	437	23.6%

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	7,636	0.9%	0%
beta2-Adrenergic agonist	4,276	4.7%	1.1%
Anticholinergic	2,901	1.8%	0%
Leukotriene receptor antagonist	1,930	5%	6.2%
Kinase inhibitor	1,806	0.2%	0%
Interleukin-5 antagonist	1,753	3.7%	3.4%
Proton pump inhibitor	1,746	0.4%	0.2%
Thalidomide analog	875	0.2%	0.2%
Nonsteroidal anti-inflammatory drug	873	0.2%	0%
Serotonin reuptake inhibitor	843	0.3%	0%

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 20.2%19

2 to 110.3%36

12 to 170.3%34

18 to 448%827

45 to 6423.5%2,446

65 to 7418.3%1,904

75 and over16.3%1,700

Age not given33%3,434

Patient sex

Female53.9%5,601

Male32.6%3,393

Not given13.5%1,406

Grey bar: all 20,646,523 reports in the database. 49.4% of these reports give the United States as the country.

Questions about "Full blood count abnormal"

What does "Full 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 full blood count abnormal?

10,400 reports through June 2026 (0.1% of all reports), 802 of them in the latest 12 months.

Which drugs appear most often in these reports?

Prednisone (2,346), Albuterol (1,965), Albuterol sulfate (1,872), Tiotropium bromide (1,555) and Nucala (1,204). 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.