Hyaluronidase

Pronunciation: (HYE-al-ure-ON-i-dase)
Class: Physical adjunct

Trade Names

Amphadase
- Solution for injection 150 units/mL (bovine source)

Hylenex
- Solution for injection 150 units/mL (recombinant human)

Vitrase
- Solution for injection 200 units/mL (ovine source)
- Powder for injection, lyophilized 6,200 units (ovine source)

Pharmacology

Modifies the permeability of connective tissue through the hydrolysis of hyaluronic acid, which temporarily decreases the viscosity of the cellular cement and promotes diffusion of injected fluids or of localized transudates, thus facilitating their absorption.

Indications and Usage

As an adjunct to increase the absorption and dispersion of other injected drugs; for hypodermoclysis; as an adjunct in subcutaneous urography for improving resorption of radiopaque agents.

Unlabeled Uses

Treatment of vitreous hemorrhage and diabetic retinopathy.

Contraindications

Standard considerations.

Dosage and Administration

Absorption and Dispersion of Injected Drugs
Adults

Subcutaneous Add 50 to 300 units (typically 150 units) to the injection solution.

Hypodermoclysis
Adults

Subcutaneous 150 units will facilitate absorption of 1,000 mL or more of solution.

Children

Subcutaneous May be added to small volumes of solution (up to 200 mL), such as a small clysis for infants or solutions of drugs for subcutaneous injection. For infants and children younger than 3 yr of age, limit the volume of a single clysis to 200 mL. In premature infants or during the neonatal period, the daily dose should not exceed 25 mL/kg, and the rate of administration should not exceed 2 mL/min. For older patients, the rate and volume should not exceed those employed for IV infusion.

Urography
Adults and Children

Subcutaneous When IV administration cannot be successfully accomplished, particularly in infants and small children, inject 75 units over each scapula, followed by injection of the contrast medium at the same site.

General Advice

Before administration of any other drug(s) in combination with hyaluronidase, ensure that references have been reviewed to determine usual precautions regarding use of the other drug(s) and compatibility with hyaluronidase.
Do not administer if solution is cloudy, discolored, or contains particulate matter.

Powder for injection

Reconstitute powder for injection by adding sodium chloride 6.2 mL injection to vial. Reconstituted solution provides hyaluronidase 1,000 units/mL.
Further dilute reconstituted solution with sodium chloride solution before administration following dilution guidelines in the package insert. Withdraw desired volume of reconstituted solution from the vial using the supplied 5-micron filter needle.

Solution for injection

Following manufacturer's guidelines, withdraw desired amount of hyaluronidase solution into syringe to obtain target hyaluronidase activity.

Incompatibilities

Benzodiazepines, furosemide, and phenytoin are incompatible with hyaluronidase.

Storage/Stability

Store unopened vials of powder for injection in refrigerator (36° to 46°F). After reconstitution, store at controlled room temperature (68° to 77°F) and use within 6 h. Protect from light. Store hyaluronidase solution in refrigerator (36° to 46°F). Protect from light. Do not freeze.

Drug Interactions

Antihistamines, corticotropin, cortisone, estrogens, salicylates

Because these agents may render tissues resistant to the action of hyaluronidase, larger amounts of hyaluronidase may be required for equivalent dispersing effect.

Local anesthetics

Hastens onset of analgesia and tends to reduce swelling caused by local infiltration; however, wider spread of the local anesthetic solution increases its absorption, shortening the duration of action and increasing the incidence of systemic reaction.

Laboratory Test Interactions

None well documented.

Adverse Reactions

Dermatologic

Injection-site reactions.

Hypersensitivity

Anaphylaxis, angioedema, urticaria.

Miscellaneous

Edema.

Precautions

Monitor

Injection-site reaction

Monitor patient for reactions at injection site and for adverse reactions commonly associated with any drug coadministered with hyaluronidase.

Pregnancy

Category C .

Lactation

Undetermined.

Children

See Administration and Dosage section.

Elderly

No differences in safety and efficacy have been observed between elderly and younger adult patients.

Skin test

Preliminary skin test may be performed by an intradermal injection of approximately 0.02 mL (3 units) of a 150 units/mL solution.

Special considerations

Do not use hyaluronidase to enhance absorption and dispersion of dopamine or alpha-agonist drugs; do not inject into or around an infected or acutely inflamed area (risk of spreading of localized infection may be increased); do not use to reduce swelling of bites or stings; do not apply directly to the cornea; do not administer IV.