Reported Reactions

Drugs › Endoglycosidase

Generic name

Hyaluronidase: adverse event reports filed with FDA

1,170 reports list it as a suspect or interacting product, 2004–2026. Class: Endoglycosidase. Also reported as Hyaluronidase Inj, Hyaluronidase 150 Iu.

1,170
reports as suspect product
0% of all reports · about 53 a year
212
reports, 12 months to June 2026
297 in the 12 months before
97.3%
marked serious by the reporter
47.1% across the class
53.2%
record death among outcomes, as reported
623 reports · not verified by FDA

Between May 2004 and June 2026, 1,170 adverse event reports received by FDA list hyaluronidase, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (270) are left out of every figure here.

In the 12 months to June 2026, 212 reports listed it, down 29% from 297 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 53 reports a year and 0% of the 20,646,523 reports in the database, and 20.7% of the reports for the endoglycosidase class. How many people take it is not in the data, so a count is not a rate of occurrence.

Reporters most often recorded fatigue (35.2%), alopecia (35%) and abdominal discomfort (34.9%). A report can list several reactions, so shares add to more than 100%; 426 different terms appear across these reports. Fatigue is recorded in 35.2% of these reports, a larger share than in the median endoglycosidase drug (19.3%).

97.3% of the reports are marked serious by the reporter (47.1% across the class); 53.2% record death among the outcomes and 78.5% record hospitalisation, as reported. 62.6% of the reports came from other health professionals, and the largest patient age group is 18 to 44 (41.8%). 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

02754Jul 2021: 2Aug 2021: 16Sep 2021: 4Oct 2021: 2Nov 2021: 5Dec 2021: 22022Jan 2022: 1Feb 2022: 4Mar 2022: 5Apr 2022: 5May 2022: 15Jun 2022: 2Jul 2022: 6Aug 2022: 13Sep 2022: 7Oct 2022: 8Nov 2022: 8Dec 2022: 182023Jan 2023: 13Feb 2023: 10Mar 2023: 9Apr 2023: 15May 2023: 20Jun 2023: 24Jul 2023: 7Aug 2023: 12Sep 2023: 15Oct 2023: 17Nov 2023: 10Dec 2023: 92024Jan 2024: 15Feb 2024: 25Mar 2024: 18Apr 2024: 32May 2024: 23Jun 2024: 17Jul 2024: 49Aug 2024: 28Sep 2024: 27Oct 2024: 35Nov 2024: 18Dec 2024: 162025Jan 2025: 10Feb 2025: 14Mar 2025: 54Apr 2025: 23May 2025: 11Jun 2025: 12Jul 2025: 34Aug 2025: 20Sep 2025: 14Oct 2025: 18Nov 2025: 7Dec 2025: 332026Jan 2026: 18Feb 2026: 8Mar 2026: 7Apr 2026: 21May 2026: 16Jun 2026: 16

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

01523032004: 620042005: 72006: 202007: 1720072008: 82009: 92010: 520102011: 42012: 42014: 220142015: 302016: 62017: 1320172018: 152019: 262020: 4020202021: 662022: 922023: 16120232024: 3032025: 2502026: 862026

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Hyaluronidase reports recording the termmedian drug in endoglycosidase

  1. Fatiguetiredness35.2%412
  2. Alopeciahair loss35%410
  3. Abdominal discomfortstomach discomfort34.9%408
  4. Arthralgiajoint pain32.4%379
  5. Blood cholesterol increasedraised cholesterol32.3%378
  6. Diarrhoealoose or frequent stools32%374
  7. Headachehead pain31.8%372
  8. Arthropathy31.1%364
  9. Hypertensionhigh blood pressure31.1%364
  10. Maternal exposure during pregnancythe mother took the medicine during pregnancy30.9%362
  11. Type 2 diabetes mellitustype 2 diabetes30.7%359
  12. Dyspnoeashortness of breath30.4%356
  13. Condition aggravatedthe condition being treated got worse30.3%354
  14. Systemic lupus erythematosuslupus, an autoimmune disease29.9%350
  15. General physical health deteriorationgeneral decline in health29.1%341
  16. Asthmaasthma29%339
  17. Musculoskeletal stiffnessstiffness in muscles or joints29%339
  18. Swellingswelling29%339
  19. Decreased appetitereduced appetite28.8%337
  20. Astheniaweakness or lack of energy28.7%336
  21. Discomfortdiscomfort28.7%336
  22. Contusiona bruise28.5%334
  23. Anxietyanxiety28.2%330
  24. Rheumatic fever28%328
  25. Confusional stateconfusion27.9%327
  26. Painpain, site not specified27.9%327
  27. Pemphigus27.9%327
  28. Vomitingbeing sick27.7%324

Top 30 of 426 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 median share across the 2 drugs in the endoglycosidase class; 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

Death53.2%623
Life-threatening61.1%715
Hospitalisation (initial or prolonged)78.5%919
Disability63.1%738
Congenital anomaly24.4%286
Other serious86.1%1,007
Not serious2.7%32

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 5,659 reports in the class. 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 20.4%5
2 to 110%0
12 to 170%0
18 to 4441.8%489
45 to 6422.7%266
65 to 749.9%116
75 and over5.3%62
Age not given19.8%232

Patient sex

Female75.1%879
Male9.3%109
Not given15.6%182

Who reported

Physician28.9%338
Pharmacist0.9%10
Other health professional62.6%732
Lawyer0%0
Consumer or non-health professional5%58
Not given2.7%32

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 10.6% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Rheumatoid arthritis41135.1%
Her2 positive breast cancer423.6%
Breast cancer metastatic332.8%
Local anaesthesia302.6%
Anaesthesia211.8%
Plasma cell myeloma171.5%

The indication field is filled in by the reporter and is often blank; shares are of all 1,170 reports.

In context

MeasureHyaluronidaseEndoglycosidaseAll reports
Reports as suspect product1,1705,65920,646,523
Share of that pool—20.7%0%
Reports, latest 12 months212—1,332,454
Marked serious97.3%47.1%57.4%
Death recorded among outcomes, per 1,000 reports53215491
Hospitalisation recorded, per 1,000 reports785254213
Consumer-filed share5%27.4%45.8%
Top term, share of reportsFatigue 35.2%median 19.3%3.7%

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."

Other drugs in the endoglycosidase class

DrugName typeReportsLatest 12 monthsMarked serious
Phesgobrand4,48969434%

Ordered by report count for navigation only. 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." A brand and its generic are separate rows because reporters name them separately.

Questions about Hyaluronidase reports

How many adverse event reports has FDA received for Hyaluronidase?

1,170 reports list Hyaluronidase as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 212 of them arrived in the latest 12 months. Another 270 list it only as a concomitant medication.

What reactions are recorded in Hyaluronidase reports?

fatigue (35.2%), alopecia (35%), abdominal discomfort (34.9%), arthralgia (32.4%) and blood cholesterol increased (32.3%). 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 Hyaluronidase was responsible.

How serious are the reports?

97.3% are marked serious by the reporter. Among the outcomes recorded, 53.2% of reports include death and 78.5% 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?

other health professional (62.6%), physician (28.9%) and consumer or non-health professional (5%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Hyaluronidase rising?

212 reports in the 12 months to June 2026, down 29% from 297 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 Hyaluronidase 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 Hyaluronidase?

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 Hyaluronidase as a suspect or interacting product; reports listing it only as a concomitant medication (270) 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.