Presentation
- 15mg tablets
- 50mg vials
Note: Folinic acid is not interchangeable with folic acid
Vials Only - Keep Refrigerated
Role
- To decrease absorption and bypass inhibition of dihydrofolate reductase following high-risk acute methotrexate overdose involving staggered ingestions over 36h, massive ingestions > 1000mg (>5mg/kg in children) or any acute ingestion in patients with renal impairment.
- To bypass methotrexate’s inhibition of dihydrofolate reductase and restore reduced folate stores in established methotrexate toxicity.
- Co-factor in the treatment of methanol toxicity.
Dose
Management of high-risk acute methotrexate overdose
- 15mg PO followed by 15mg IV q6h for 3 days (initial dose is given orally to reduce ongoing methotrexate absorption from GI tract)
Management of established methotrexate toxicity
- 15mg IV/PO q6h until bone marrow recovers and mucosal ulceration resolves
Management of methanol toxicity
- 50mg IV q6h
Stocking recommendations
| Tertiary centre | Regional centre | Rural centre | Remote centre |
|---|---|---|---|
|
10 x 50mg vials and 10 x 15mg tablets |
10 x 50mg vials and 0 – 10 x 15mg tablets | 0 – 10 x 50mg vials | 0 vials |
Rationale
Patients with established methotrexate toxicity have bone marrow suppression which would warrant management in at least a regional centre. The IV preparation can be given orally if the tablet formulation is unavailable.
Disclaimer
Fact sheet developed by Queensland Poisons Information Centre.
This fact sheet is about the use of these antidotes in Australia, and may not apply to other countries. Children’s Health Queensland Hospital and Health Service cannot be held responsible for the accuracy of information, omissions of information, or any actions that may be taken as a consequence of reading this fact sheet.