Reported Reactions

Drugs

Product name as reported

Fuzeon: adverse event reports filed with FDA

1,212 reports list it as a suspect or interacting product, 2004–2026.

1,212
reports as suspect product
0% of all reports · about 54 a year
11
reports, 12 months to June 2026
12 in the 12 months before
82.3%
marked serious by the reporter
57.4% across all reports
9.4%
record death among outcomes, as reported
114 reports · not verified by FDA

1,212 adverse event reports received by FDA list the product name "Fuzeon" as reporters wrote it as a suspect or interacting product, from January 2004 to June 2026. A further 580 reports list it only as a concomitant medication, and those are not counted in the figures on this page.

In the 12 months to June 2026, 11 reports listed it, close to the 12 of 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 54 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.

Reporters most often recorded injection site reaction (14.7%), pyrexia (5.8%) and injection site pain (5.2%). A report can list several reactions, so shares add to more than 100%; 383 different terms appear across these reports. Injection site reaction is recorded in 14.7% of these reports, against 0.3% of all reports in the database.

82.3% of the reports are marked serious by the reporter; 9.4% record death among the outcomes and 28.5% record hospitalisation, as reported. 30.7% of the reports came from physicians, and the largest patient age group is 45 to 64 (27.8%). 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

0612Jul 2021: 0Aug 2021: 1Sep 2021: 0Oct 2021: 0Nov 2021: 0Dec 2021: 02022Jan 2022: 3Feb 2022: 0Mar 2022: 1Apr 2022: 0May 2022: 1Jun 2022: 1Jul 2022: 4Aug 2022: 8Sep 2022: 1Oct 2022: 1Nov 2022: 0Dec 2022: 02023Jan 2023: 0Feb 2023: 0Mar 2023: 0Apr 2023: 3May 2023: 3Jun 2023: 2Jul 2023: 1Aug 2023: 0Sep 2023: 1Oct 2023: 0Nov 2023: 4Dec 2023: 122024Jan 2024: 0Feb 2024: 1Mar 2024: 6Apr 2024: 1May 2024: 4Jun 2024: 0Jul 2024: 0Aug 2024: 0Sep 2024: 0Oct 2024: 3Nov 2024: 0Dec 2024: 32025Jan 2025: 0Feb 2025: 2Mar 2025: 2Apr 2025: 1May 2025: 1Jun 2025: 0Jul 2025: 1Aug 2025: 0Sep 2025: 0Oct 2025: 0Nov 2025: 0Dec 2025: 02026Jan 2026: 0Feb 2026: 0Mar 2026: 2Apr 2026: 0May 2026: 6Jun 2026: 2

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

0991982004: 19820042005: 1852006: 1492007: 8920072008: 642009: 482010: 4220102011: 152012: 382013: 1220132014: 212015: 122016: 1420162017: 1662018: 182019: 4720192020: 32021: 102022: 2020222023: 262024: 182025: 720252026: 10

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Fuzeon reports recording the termall reports in the database

  1. Injection site reactiona reaction where the injection was given14.7%178
  2. Pyrexiafever5.8%70
  3. Injection site painpain where the injection was given5.2%63
  4. Medication errora mistake in prescribing, dispensing or taking a medicine4%48
  5. Drug ineffectivethe medicine did not work as expected3.1%38
  6. Deaththe patient died; cause not stated by this term3%36
  7. Foetal exposure during pregnancythe unborn baby was exposed to the medicine2.9%35
  8. Injection site erythemaredness where the injection was given2.6%31
  9. No adverse eventno adverse event was reported2.6%31
  10. Product quality issuea problem with the product itself2.4%29
  11. Plagiocephaly2.3%28
  12. Injection site swellingswelling where the injection was given2.1%26
  13. Neutropenialow neutrophils, a type of white blood cell2.1%26
  14. Pneumonialung infection2.1%26
  15. No adverse effect2.1%25
  16. Painpain, site not specified2%24
  17. Rashskin rash2%24
  18. Vomitingbeing sick2%24
  19. Dyspnoeashortness of breath1.9%23
  20. Erythemaskin redness1.9%23
  21. Hypersensitivityan allergic-type reaction1.9%23
  22. Nauseafeeling sick1.9%23
  23. Injection site pruritusitching where the injection was given1.8%22
  24. Multiple-drug resistance1.8%22
  25. Depressionlow mood1.7%21
  26. Leukopenialow white blood cells1.7%21
  27. Pancytopenialow counts of all blood cells1.7%21

Top 30 of 383 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

Death9.4%114
Life-threatening4%48
Hospitalisation (initial or prolonged)28.5%346
Disability3.1%37
Congenital anomaly4.7%57
Other serious47%570
Not serious17.7%215

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 20.9%11
2 to 110.4%5
12 to 170.7%9
18 to 4421.7%263
45 to 6427.8%337
65 to 740.9%11
75 and over0.1%1
Age not given47.4%575

Patient sex

Female18.4%223
Male67.5%818
Not given14.1%171

Who reported

Physician30.7%372
Pharmacist11.6%140
Other health professional22.8%276
Lawyer0.1%1
Consumer or non-health professional24.5%297
Not given10.4%126

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 42.2% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Hiv infection46938.7%
Hiv test positive292.4%
Acquired immunodeficiency syndrome181.5%
Maternal exposure timing unspecified50.4%
Antiretroviral therapy40.3%
Retroviral infection40.3%

The indication field is filled in by the reporter and is often blank; shares are of all 1,212 reports.

In context

MeasureFuzeonAll reports
Reports as suspect product1,21220,646,523
Share of that pool—0%
Reports, latest 12 months111,332,454
Marked serious82.3%57.4%
Death recorded among outcomes, per 1,000 reports9491
Hospitalisation recorded, per 1,000 reports285213
Consumer-filed share24.5%45.8%
Top term, share of reportsInjection site reaction 14.7%0.3%

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 Fuzeon reports

How many adverse event reports has FDA received for Fuzeon?

1,212 reports list Fuzeon as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 11 of them arrived in the latest 12 months. Another 580 list it only as a concomitant medication.

What reactions are recorded in Fuzeon reports?

injection site reaction (14.7%), pyrexia (5.8%), injection site pain (5.2%), medication error (4%) and drug ineffective (3.1%). 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 Fuzeon was responsible.

How serious are the reports?

82.3% are marked serious by the reporter. Among the outcomes recorded, 9.4% of reports include death and 28.5% 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?

physician (30.7%), consumer or non-health professional (24.5%) and other health professional (22.8%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Fuzeon rising?

11 reports in the 12 months to June 2026, close to the 12 of 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 Fuzeon 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 Fuzeon?

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 Fuzeon as a suspect or interacting product; reports listing it only as a concomitant medication (580) 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.