DRUG SUPPLIED DOSE COMMENTS
GLUCARPIDASE (Paeds)
(Voraxaze, carboxypeptidase)

Mechanism of action:

Indicated for the treatment of toxic plasma methotrexate concentrations in patients with delayed methotrexate clearance due to impaired renal function. Glucarpidase rapidly hydrolyzes methotrexate to inactive metabolites.


Ref: 450, 451, 452, 519



Last update: 2022-01-04		 Injection: 1000 unit vial available only through Special Access Program.

Emergency stock for western Canada is maintained at McKesson Wholesale but will only be released upon approval by Health Canada		 Methotrexate toxicity: 50 units/kg/dose IV once

Intrathecal methotrexate overdose: 2000 units/dose intrathecally once		 Indicated for the treatment of toxic plasma methotrexate concentrations in patients with delayed methotrexate clearance and/or in the presence of deteriorating renal function. Refer to individual chemotherapy protocol for glucarpidase indications.

Glucarpidase should be administered within 48-60 hours of start of methotrexate.

Glucarpidase rapidly hydrolyzes methotrexate to inactive metabolites.

Do not administer leucovorin within 2 hours of glucarpidase.

Measurement of methotrexate serum levels using immunoassays is unreliable for samples collected within 48 hours following glucarpidase administration and levels will appear falsely high due to the interference of the inactive metabolite of methotrexate (this method is used at BCCH).

Anaphylaxis is rare (<1%). Paresthesias, flushing, nausea, vomiting, hypotension, headache may occur.

Standard Prescription:

Glucarpidase __ units IV {intrathecal} (__ units /kg /dose), one dose.
Glucarpidase __ units intrathecal, one dose.