Hyalase (Hyaluronidase)

Hyalase is employed as an adjunctive enzyme in various clinical settings where enhanced dispersion of injected substances is desired. Typical applications include:

• Facilitating subcutaneous fluid absorption during regional anesthesia procedures.
• Improving the spread of local anesthetic solutions for peripheral nerve blocks.
• Assisting the dispersion of contrast media during radiographic imaging studies.
• Enhancing the distribution of chemotherapeutic agents in intralesional cancer therapy.
• Supporting the breakdown of hyaluronic acid accumulations in certain ophthalmic procedures.
• Promoting more uniform infiltration of antibiotics in soft‑tissue infection management.
• Aiding the diffusion of hyaluronic‑acid‑based fillers during dermatologic procedures when rapid dispersion is required.

• Hyalase contains hyaluronidase, an enzyme that hydrolyzes the glycosidic bonds of hyaluronic acid, a major component of the extracellular matrix. By depolymerizing hyaluronic acid, the enzyme reduces viscosity of interstitial fluid and temporarily opens the intercellular spaces, increasing tissue permeability. This enzymatic action facilitates the rapid dispersion and absorption of co‑administered drugs, fluids, or contrast agents at the injection site.

Adverse reactions to Hyalase are generally related to its enzymatic activity and the injection process. Reported events range from mild, transient symptoms to rare serious complications.

Common

• Localized pain, burning, or stinging at the injection site.
• Mild erythema or swelling around the administration area.
• Transient itching or rash that resolves without intervention.
• Temporary bruising or hematoma formation at the injection site.
• Mild headache or dizziness occurring shortly after administration.

Serious

• Allergic hypersensitivity reactions, including urticaria, angioedema, or anaphylaxis.
• Significant tissue necrosis or ulceration at the injection site.
• Systemic effects such as hypotension or cardiovascular instability.
• Development of compartment syndrome due to excessive tissue swelling.

When using Hyalase, clinicians should consider several precautionary measures to minimize risks and ensure appropriate patient selection.

• Verify absence of known hypersensitivity to hyaluronidase or any component of the formulation.
• Assess patient history for previous allergic reactions to enzymes or biologic products.
• Use the lowest effective dose and limit the volume of injection to the recommended anatomical area.
• Avoid intravascular administration to reduce the chance of systemic exposure.
• Monitor patients for immediate signs of reaction during and after injection.
• Exercise caution in patients with cardiovascular instability or uncontrolled hypertension.

Hyalase may interact with other agents administered concurrently, influencing their distribution or increasing the risk of adverse events.

Avoid

• Co‑administration with high‑dose vasopressors, which can exacerbate hypotensive reactions.
• Simultaneous injection of other enzyme preparations that may potentiate tissue breakdown.
• Avoid use immediately before or after intravascular contrast injection, which may alter vascular permeability.

Use with caution

• Concurrent use of local anesthetics, as altered absorption may affect onset and duration.
• Administration with contrast media in imaging studies; monitor for unexpected diffusion patterns.
• Use in patients receiving anticoagulants, observing for increased bleeding at the injection site.
• Combine with systemic steroids cautiously, as hyaluronidase may enhance steroid dispersion and systemic exposure.