Antidotes ATSDR

There is no proven antidote for hydrogen sulfide poisoning. Treatment consists of supportive measures such as evaluating and supporting airway, breathing, and circulation (ATSDR 1994). Sodium nitrite may or may not be an effective antidote, but if proper precautions in administration are observed, intravenous administration of sodium nitrite may help some hydrogen sulfide poisoned persons (Hall 1996 Hall and Rumack 1997). Hyperbaric oxygen therapy is controversial, but it may be effective for patients not treated successfully by other measures (ATSDR 1994). 

The choice of appropriate treatment for nerve agent intoxication depends on the agent as well as extent and route(s) of exposure. Very mild exposure to nerve agent vapor may necessitate only decontamination and observation severe exposure to vapor or liquid requires immediate decontamination, antidote administration, artificial respiration, monitoring, and supportive therapy over hours to multiple days (ATSDR, 2007 Sidell, 1997 Vale et al, 2007 Pulley and Jones, 2008). Convenient triage classifications have been developed by ATSDR (2007) in collaboration with the US Army Medical Research Institute of Chemical Defense. 

Individuals exposed to vapor and exhibiting miosis only or miosis and rhinorrhea only do not usually require antidote treatment and will resolve without medical intervention (Cannard, 2006 ATSDR, 2007), but they should be observed. If rhinorrhea is problematic in these vapor-only cases, then ATSDR (2007) advises intramuscular atropine (0.05mg/kg pediatric 2.0 mg adult) to relieve signs, followed by patient discharge. If eye pain/headache or nausea is problematic in vapor-only... 

If liquid/droplet exposure is known or suspected in an individual exhibiting miosis only or miosis and rhinorrhea only, it is recommended that the individual receive no antidote treatment but be closely observed for at least 18 h, because toxic effects of liquid percutaneous exposure may not manifest for several hours (Sidell, 1997 Cannard, 2006). Toxic effects from vapor-only exposure usually occur quickly (within minutes) (Sidell, 1997). Current medical management guidelines and recommended medication protocols are summarized in ATSDR (2007), Vale et al. (2007), and Pulley and Jones (2008). The ATSDR antidote treatment protocol for civilian emergency management is summarized in Table 9.7. For additional information about antidotal treatment, readers are referred to Chapters 67, 68, and 71 of this volume. 

---