1g/5mL ampoule


As an adjunct in the treatment of severe sodium valproate toxicity evidenced by valproate concentration > 850 mg/L or cardiovascular collapse and worsening acidaemia.

Medication box with the name L-Carn. A vial next to the box.

Consultation with a clinical toxicologist is recommended through local toxicology service or Poisons Information Centre 13 11 26.


  • 100mg/kg IV loading dose (max 6g); then
  • 50mg/kg Q8H (max 3g)

Stocking recommendations

Tertiary centre Regional centre Rural centre Remote centre
10 vials 10 vials 0 vials 0 vials


The role of L-carnitine in valproate toxicity is controversial. It reduces the production of a toxic metabolite, but whether this leads to improved outcomes is unclear. Given it is a low cost, safe therapy with scientific plausibility, it is recommended in cases of severe toxicity. Patients with severe valproate toxicity will need to be managed in facilities with haemodialysis. Initiation of L-carnitine therapy can be delayed until transfer to a dialysis centre has occurred


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.

Last updated: July 2023