Hydrogen Sulfide Toxicity Medication
- Author: Chip Gresham, MD, FACEM; Chief Editor: Asim Tarabar, MD more...
Antidotal treatment of hydrogen sulfide (H2 S) poisoning is based on the creation of methemoglobinemia. Symptomatic treatment includes the use of bronchodilators for patients with bronchospasm.
Nitrite administration leads to formation of methemoglobinemia. H2 S has a much greater affinity for methemoglobin than for cellular cytochromes, leading to lower metabolic toxicity.
Although approved for use in cyanide poisoning, sodium nitrite is the initial drug of choice for hydrogen sulfide poisoning. Because high methemoglobin concentrations can cause fatal reduction of oxygenation and perfusion, methemoglobin concentrations should be closely monitored and kept below 30%.
Sodium thiosulfate should not be used in the treatment of hydrogen sulfide poisoning. In the classic cyanide antidote kit, sodium nitrite and sodium thiosulfate are provided. The nitrites cause the formation of methemoglobinemia, scavenging both cyanide and hydrogen sulfide. In cyanide poisoning, sodium thiosulfate enhances the activity of the enzyme rhodanese, a mammalian enzyme that likely evolved in response to the ubiquitous presence of cyanide in nature. Rhodanese catalyzes the transfer of sulfate from sodium thiosulfate to cyanide to form thiocyanate, a less toxic form that is excreted by the kidneys. This does not share the crossover treatment that sodium nitrites do with hydrogen sulfide (ie, it is useless in hydrogen sulfide poisoning).
Goode E. Chemical Suicides, Popular in Japan, Are Increasing in the U.S. NY Times, June 18, 2011. Available at http://www.nytimes.com/2011/06/19/us/19chemical.html?pagewanted=all.
Fuller DC, Suruda AJ. Occupationally related hydrogen sulfide deaths in the United States from 1984 to 1994. J Occup Environ Med. 2000 Sep. 42(9):939-42. [Medline].
Sams RN, Carver HW 2nd, Catanese C, Gilson T. Suicide with hydrogen sulfide. Am J Forensic Med Pathol. 2013 Jun. 34(2):81-2. [Medline].