Hylenex Reconstitution
Hylenex (recombinant hyaluronidase) does not require reconstitution—it is supplied as a sterile, ready-to-use solution. 1
Product Formulation
Hylenex recombinant comes pre-formulated as a clear, colorless, nonpreserved solution at a concentration of 150 USP units per mL 1. The product contains:
- Active ingredient: 150 USP units recombinant human hyaluronidase per mL
- Excipients:
- 8.5 mg sodium chloride
- 1.4 mg dibasic sodium phosphate
- 1 mg albumin human
- 1.5 mg L-methionine
- 0.2 mg polysorbate 80
- Hydrochloric acid and sodium hydroxide (for pH adjustment)
- pH: Approximately 7.0
- Osmolality: 280-340 mOsm/kg 1
Clinical Application
When using Hylenex for subcutaneous fluid administration, the standard approach is:
- Administer 1 mL (150 units) subcutaneously prior to fluid infusion 2, 3
- The enzyme facilitates diffusion of subsequently administered fluids through subcutaneous tissues
- For chemotherapy extravasation with vinca alkaloids, inject 1-6 mL of the 150 U/mL solution through the existing IV line, with the usual dose being 1 mL of hyaluronidase solution for each 1 mL of extravasated drug 4
Important Safety Considerations
Contraindication: Do not use in patients with known bee venom allergy due to cross-reactivity 5, 1. A preliminary intradermal skin test using 0.02 mL (3 Units) can be performed if hypersensitivity is suspected—a positive reaction shows a wheal with pseudopods within 5 minutes 1.
The ready-to-use formulation eliminates preparation errors and allows for immediate administration when needed, which is particularly critical in emergency situations such as filler-related vascular complications where early intervention (within 6 hours) significantly improves outcomes 6.