UMEM Educational Pearls

Category: Toxicology

Title: Methylene Blue: New use for an old antidote

Keywords: Methylene Blue (PubMed Search)

Posted: 1/24/2019 by Kathy Prybys, MD (Emailed: 1/31/2019) (Updated: 1/31/2019)
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Question

Most clinicians are familiar with use of methylene blue for the treatment of methemoglobinemia, as a urinary analgesic, anti-infective, and anti-spasmodic agent, or for its use in endoscopy as a gastrointestinal dye, but this compound also has a role as a rescue antidote in life threatening poisonings causing refractory shock states and other shock states.

  • Nitric Oxide plays an important role in the regulation of vascular tone.
  • Metylene blue inhibits the NO-cGMP pathway which decreases vasodilitation and increases responsiveness to vasopressors.
  • Several case reports document hemodynamic improvement in recalcitrant shock states form calcium channel and beta blockers despite multiple therapies including vasopressors, glucagon, high dose insulin, and fat emulsion therapy.
  • Dosing is 1-2 mg/kg (0.1-0.2 ml/kg) of 1% solution given IV over 5 minutes folllowed by continuous infusion.

 

Bottom Line: 

Methylene blue should be considered when standard treatment of distributive shock fails. 

 

 

Answer

Image result for methylene blue

References

Methylene Blue for Distributive Shock: a Potential New Use of An Old Antidote. Jang DH, Nelson LS, Hoffman RS. J Med Toxicol. 2013;9(3):242-9.

Methylene blue used in treatment of refractory shock resulting from drug poisoning. Fischer J. Taori G. et al. Clin Toxicol 2014 Jan;52(1) 63-65.

Calcium channel antagonist and beta blocker overdoses: antidotes and adjunct therapies. Graudins A, Lee HM, Druda D. Br J Clin Pharmacol. 2016 Mar 81(3):453-61.

A Review of Methylene Blue Treatment for Cardiovascular Collapse. Lo A, Jean CY, et al. Journal of Emerg Med. May 2014. Vol 46 (6): 670-679.

A Systematic Analysis of methylene Blue  for Drug-Induced Shock. Warrick BJ, Tataru AP, Smolinske S. Clin Toxicol 2016 Aug;54(7):547-55.