hyaluronidase (Amphadase, Hylenex Recombinant, Vitrase)

Dosing and uses of Amphadase, Hylenex Recombinant (hyaluronidase)

• Adult
• Pediatric

 

Adult dosage forms and strengths

injectable solution

• 150unit/mL
• 200unit/mL

 

Skin Test

0.02 (3 units) of 150 units/mL solution intredermally; a wheal with pseudopods appearing within 5 min and persisting for 20-30 min with itching will indicate positive hypersensitivity reaction

 

Absorption/Dispersion of Injected Drugs

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

 

Hypodermoclysis

Amphadase/Hylenex: Inject 150 units prior to SC fluid administration; this will facilitate absorption of 1000 mL or more of solution

Vitrase: Inject 200 units prior to SC fluid administration; this will facilitate absorption of 1000 mL or more of solution

 

Adjunct Subcutaneous Urography

Improves resorption of radiopaque agents; indicated when intravenous administration cannot be successfully accomplished, with the patient prone

Inject 75 units SC over each scapula, followed by injection of the contrast medium at the same sites

 

Pediatric dosage forms and strengths

injectable solution

• 150unit/mL
• 200unit/mL

 

Skin Test

0.02 (3 units) of 150 units/mL solution intradermally; a wheal with pseudopods appearing within 5 min and persisting for 20-30 min with itching will indicate positive hypersensitivity reaction

 

Hypodermoclysis

Children > 3 years: May be added to small volumes of solution (up to 200 mL), such as or solutions of drugs for SC injection

Infants and children < 3 years: Volume of a single clysis should be limited to 200 mL

For premature infants or during the neonatal period: Do not exceed a daily dosage of 25 mL/kg of body weight; rate of administration should not be greater than 2 mL/min

 

Adjunct in Subcutaneous Urography

Used when IV administration cannot be successfully accomplished, particularly in infants and small children, with the patient prone

Inject 75 units SC over each scapula, followed by injection of the contrast medium at the same sites

 

Amphadase, Hylenex Recombinant (hyaluronidase) adverse (side) effects

<1%

Angioedema, urticaria, allergic reactions (<0.1%)

 

Frequency not defined

Edema

Local injection site reactions

 

Warnings

Contraindications

Hypersensitivity

 

Cautions

Do not use to enhance dispersion and absorption of dopamine &/or alpha agonists

Not for IV use; effects relative to dispersion and absorption of other drugs are not produced when it is administered IV because enzyme is rapidly inactivated

Do not use in/around inflamed/infected areas

Not for reducing swelling due to stings/bites

Do not use directly on cornea; not for topical use

Furosemide, benzodiazepines & phenytoin incompatible with hyaluronidase

Hastens onset and shortens duration of effect, increases incidence if systemic reactions with local anesthetics

Large doses of salicylates may require larger amount of hyaluronidase for equivalent dispersing effect

 

Pregnancy and lactation

Pregnancy category: C

Lactation: It is not known whether hyaluronidase is excreted in human milk; caution should be exercised

 

Pregnancy categories

A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

NA: Information not available.

 

Pharmacology of Amphadase, Hylenex Recombinant (hyaluronidase)

Mechanism of action

Dispersion agent, which modifies permeability of connective tissue through hydrolysis of hyaluronic acid, a polysaccharide found in the intercellular ground substance of connective tissue, and of certain specialized tissues, such as the umbilical cord and vitreous humor

Amphadase: Purified preparation of bovine testicular hyaluronidase

Hylenex: Purified preparation of the enzyme recombinant human hyaluronidase

Vitrase: Purified preparation of ovine testicular hyaluronidase

 

Pharmacokinetics

Onset of action: Immediate (SC)

Duration: 24-48 hr