Reported Reactions

Drugs

Product name as reported

Procarbazine: adverse event reports filed with FDA

2,826 reports list it as a suspect or interacting product, 2004–2026. Also reported as Procarbazine /00091702/.

2,826
reports as suspect product
0% of all reports · about 126 a year
150
reports, 12 months to June 2026
195 in the 12 months before
98.3%
marked serious by the reporter
57.4% across all reports
31.8%
record death among outcomes, as reported
900 reports · not verified by FDA

Between February 2004 and June 2026, 2,826 adverse event reports received by FDA list the product name "Procarbazine" as reporters wrote it as a suspect or interacting product. Reports that mention it only as a concomitant medication (477) are left out of every figure here.

In the 12 months to June 2026, 150 reports listed it, down 23% from 195 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 126 reports a year and 0% of the 20,646,523 reports in the database. How many people take it is not in the data, so a count is not a rate of occurrence.

The reactions recorded most often are off label use (10%), acute myeloid leukaemia (8.1%) and neutropenia (7.9%). A report can list several reactions, so shares add to more than 100%; 630 different terms appear across these reports. Off label use is recorded in 10% of these reports, against 4.1% of all reports in the database.

98.3% of the reports are marked serious by the reporter; 31.8% record death among the outcomes and 27.8% record hospitalisation, as reported. 54.2% of the reports came from other health professionals, and the largest patient age group is 18 to 44 (21.5%). 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

02345Jul 2021: 29Aug 2021: 16Sep 2021: 25Oct 2021: 17Nov 2021: 24Dec 2021: 232022Jan 2022: 9Feb 2022: 11Mar 2022: 19Apr 2022: 21May 2022: 20Jun 2022: 13Jul 2022: 34Aug 2022: 19Sep 2022: 7Oct 2022: 17Nov 2022: 37Dec 2022: 162023Jan 2023: 12Feb 2023: 18Mar 2023: 10Apr 2023: 7May 2023: 5Jun 2023: 16Jul 2023: 20Aug 2023: 23Sep 2023: 16Oct 2023: 8Nov 2023: 16Dec 2023: 52024Jan 2024: 13Feb 2024: 11Mar 2024: 7Apr 2024: 11May 2024: 17Jun 2024: 8Jul 2024: 27Aug 2024: 24Sep 2024: 25Oct 2024: 23Nov 2024: 7Dec 2024: 122025Jan 2025: 6Feb 2025: 12Mar 2025: 4Apr 2025: 13May 2025: 10Jun 2025: 32Jul 2025: 45Aug 2025: 11Sep 2025: 16Oct 2025: 11Nov 2025: 6Dec 2025: 82026Jan 2026: 9Feb 2026: 10Mar 2026: 15Apr 2026: 11May 2026: 7Jun 2026: 1

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

01362712004: 4020042005: 332006: 202007: 4420072008: 252009: 472010: 2420102011: 362012: 642013: 15420132014: 692015: 1012016: 15720162017: 2712018: 2122019: 22320192020: 2712021: 2442022: 22320222023: 1562024: 1852025: 17420252026: 53

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Procarbazine reports recording the termall reports in the database

  1. Off label useused for a purpose or in a way not on the label10%284
  2. Neutropenialow neutrophils, a type of white blood cell7.9%224
  3. Febrile neutropeniafever with low white blood cells5%141
  4. Product use in unapproved indicationused for a purpose not on the label4.8%136
  5. Drug ineffectivethe medicine did not work as expected4.8%135
  6. Pyrexiafever4.8%135
  7. Thrombocytopenialow platelets4.5%127
  8. Disease progressionthe disease advanced4.1%115
  9. Infectionan infection, type not specified3.7%104
  10. Anaemialow red blood cells3.5%100
  11. Hepatitis B reactivation3.4%97
  12. Pneumonialung infection3.4%95
  13. Sepsisa severe body-wide response to infection3.3%94
  14. Vomitingbeing sick3.3%93
  15. Hodgkin's disease3.1%88
  16. Nauseafeeling sick3%84
  17. Fatiguetiredness2.6%74
  18. Dyspnoeashortness of breath2.5%70
  19. Respiratory failurethe lungs could not supply enough oxygen2.4%69
  20. Toxicity to various agentspoisoning or toxic effect of one or more substances2.4%67
  21. Neuropathy peripheralnerve damage in hands or feet2.3%65
  22. Deaththe patient died; cause not stated by this term2.1%60
  23. General physical health deteriorationgeneral decline in health2.1%59
  24. Septic shockshock arising from infection2.1%58
  25. Neutropenic infection2%56

Top 30 of 630 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the share of all reports in the database; it describes the reports, not the patients. 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."

Outcomes recorded

Death31.8%900
Life-threatening5.8%163
Hospitalisation (initial or prolonged)27.8%785
Disability0.9%25
Congenital anomaly0.1%3
Other serious69%1,950
Not serious1.7%47

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 20,646,523 reports. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 20.8%23
2 to 112.2%61
12 to 174%112
18 to 4421.5%609
45 to 6420.3%574
65 to 746.8%193
75 and over4.5%128
Age not given39.8%1,126

Patient sex

Female28.6%808
Male37.2%1,052
Not given34.2%966

Who reported

Physician34.1%963
Pharmacist3.5%98
Other health professional54.2%1,533
Lawyer0.2%5
Consumer or non-health professional4%113
Not given4%114

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 20.3% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Hodgkin's disease1,10539.1%
Central nervous system lymphoma29110.3%
Non-hodgkin's lymphoma1113.9%
Hodgkin's disease1073.8%
Diffuse large b-cell lymphoma973.4%
Lymphoma642.3%

The indication field is filled in by the reporter and is often blank; shares are of all 2,826 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Procarbazine reports
Vincristine1,63858%
Etoposide1,50653.3%
Cyclophosphamide1,47252.1%
Prednisone1,42450.4%
Bleomycin1,07638.1%
Doxorubicin90932.2%
Rituximab78627.8%
Methotrexate62922.3%
Vincristine sulfate60421.4%
Vinblastine58020.5%

Other products listed in reports where Procarbazine is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

MeasureProcarbazineAll reports
Reports as suspect product2,82620,646,523
Share of that pool—0%
Reports, latest 12 months1501,332,454
Marked serious98.3%57.4%
Death recorded among outcomes, per 1,000 reports31891
Hospitalisation recorded, per 1,000 reports278213
Consumer-filed share4%45.8%
Top term, share of reportsOff label use 10%4.1%

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. 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."

Questions about Procarbazine reports

How many adverse event reports has FDA received for Procarbazine?

2,826 reports list Procarbazine as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 150 of them arrived in the latest 12 months. Another 477 list it only as a concomitant medication.

What reactions are recorded in Procarbazine reports?

off label use (10%), acute myeloid leukaemia (8.1%), neutropenia (7.9%), febrile neutropenia (5%) and second primary malignancy (5%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Procarbazine was responsible.

How serious are the reports?

98.3% are marked serious by the reporter. Among the outcomes recorded, 31.8% of reports include death and 27.8% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

other health professional (54.2%), physician (34.1%) and not given (4%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Procarbazine rising?

150 reports in the 12 months to June 2026, down 23% from 195 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Procarbazine was responsible for these reactions?

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." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Procarbazine?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

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. A report counts here when it lists Procarbazine as a suspect or interacting product; reports listing it only as a concomitant medication (477) are excluded. 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.