What the label lists and what reports show
Hyaluronidase side effects
Hyaluronidase's FDA label: “The most frequently reported adverse reactions have been local injection site reactions.” FAERS holds 1,184 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is fatigue (301 reports).
- No generic listed
Check it at the source: the hyaluronidase FDA label on DailyMed (effective February 1, 2024, Amphastar Pharmaceuticals, Inc.); the FDA FAERS public dashboard.
What does the label list?
From the label: adverse reactionsThe most frequently reported adverse reactions have been local injection site reactions.
From the label: adverse reactions, continuedThe following adverse reactions have been identified during post-approval use of hyaluronidase products. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. The most frequently reported adverse reactions have been local injection site reactions. Hyaluronidase has been reported to enhance the adverse reactions associated with co-administered drug products. Edema has been reported most frequently in association with hypodermoclysis. Allergic reactions (urticaria, angioedema) have been reported in less than 0.1% of patients receiving hyaluronidase. Anaphylactic-like reactions following retrobulbar block or intravenous injections have occurred, rarely. Allergic and anaphylactic-like reactions have been reported, rarely ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Amphastar Pharmaceuticals, Inc. at 1-800-423-4136 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
Source: FDA drug label, Amphastar Pharmaceuticals, Inc., effective February 1, 2024 (SPL set 8396ea96-7cb5-4e26-87a4-90bca9c3c6dd), via openFDA; the full label on DailyMed
What do FAERS reports show?
1,184 reports list hyaluronidase among the medicines taken, each a report of something that happened, not proof the medicine caused it; 523 are coded as a death and 690 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 25 reactions below, none is named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Hyaluronidase: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions