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Hylenex Side Effects

Generic Name: hyaluronidase

Note: This page contains information about the side effects of hyaluronidase. Some of the dosage forms included on this document may not apply to the brand name Hylenex.

For the Consumer

Applies to hyaluronidase: powder for solution, solution

In addition to its needed effects, some unwanted effects may be caused by hyaluronidase (the active ingredient contained in Hylenex). In the event that any of these side effects do occur, they may require medical attention.

If any of the following side effects occur while taking hyaluronidase, check with your doctor or nurse immediately:

  • Cough
  • difficulty swallowing
  • dizziness
  • fast heartbeat
  • hives or welts
  • itching
  • large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • redness of the skin
  • skin rash
  • tightness in the chest
  • unusual tiredness or weakness

If any of the following symptoms of overdose occur while taking hyaluronidase, get emergency help immediately:

Symptoms of overdose:
  • Blurred vision
  • chills
  • confusion
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • fast, pounding, or irregular heartbeat or pulse
  • nausea or vomiting
  • redness of the skin
  • sweating
  • swelling
  • unusual tiredness or weakness
  • unusually warm skin

Minor Side Effects

Some of the side effects that can occur with hyaluronidase may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common:
  • Bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site

For Healthcare Professionals

Applies to hyaluronidase: injectable powder for injection, injectable solution


Local reactions are the most common side effects. The most common side effect during hypodermoclysis is edema.[Ref]


Hyaluronidase (the active ingredient contained in Hylenex) increases the side effects of coadministered drugs.[Ref]


Hypersensitivity reactions have included urticaria and angioedema in less than 0.1% of patients. Anaphylactic-like reactions have rarely been reported after intravenous or retrobulbar injection.[Ref]

One clinic has reported a possible increase in cases of angioedema related to the use of pharmacy-compounded hyaluronidase in cataract surgery as opposed to that seen with the use of manufactured products.[Ref]


Ocular side effects have included case reports of hypersensitivity reactions after retrobulbar injections, which manifested as increased intraorbital pressure and swelling, periorbital edema, and localized pruritus.[Ref]


1. "Product Information. Vitrase (hyaluronidase)." Allergan Inc, Irvine, CA.

2. Eberhart AH, Weiler CR, Erie JC "Angioedema related to the use of hyaluronidase in cataract surgery." Am J Ophthalmol 138 (2004): 142-3

3. Minning CA Jr "Hyaluronidase allergy simulating expulsive choroidal hemorrhage." Arch Ophthalmol 112 (1994): 585-6

Not all side effects for Hylenex may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.