Determination of median effective dose (ED₅₀) of scorpion antivenom against scorpion envenomation using a newly developed formula

Abstract

Background About 50 species of scorpions cause fatal scorpionism worldwide. Most of these are members of the Buthidae family, and include, among others, Mesobuthus eupeus , Androctonus crassicauda , Leiurus abdullahbayrami , Leiurus quinquestriatus , Tityus pachyurus and Androctonus australis . Because high doses of scorpion venom and antivenom can cause death and hypersensitive reactions, there is a need to develop a formula that can be used to calculate both lethal and effective doses for scorpion venom and antivenom, respectively, thereby obviating the need for laboratory experiments. Methods In view of this, a literature search was carried out with the aim of modifying the formula ( ) for calculation of the median lethal dose (LD 50 ) of scorpion venom and the ED 50 of antivenom. The human equivalent dose (HED) formula was assessed for extrapolation of LD 50 and ED 50 from animals to human for comparison and relevance with the new formula. Results The findings showed that the newly developed formula (LD 50 = ED 50 1/3 × W a × 10 −4 ) yielded results that are very close to the reported values. Therefore, the newly developed and HED formulas can be used for calculation of LD 50 and ED 50 values for scorpion venom and antivenom, respectively. Conclusion The new formula yielded better results than the HED formula, confirming its predictive validity, precision, and reliability, thereby obviating the need for rigorous experiments and justifying the principles of reduction, refinement, and replacement (3Rs).

Toxicosis of Snake, Scorpion, Honeybee, Spider, and Wasp Venoms: Part 2

“…The second dose should be 24 mg (2.4 ml). Amelioration of cardiorespiratory perturbations caused by M. eupeus envenomation in mice using polyvalent F (ab 1 ) 2 antivenin proves that neutralization factor is 1:2 to 1:25 in mice [26]. Cardio-respiratory activity modifying agents including prazosin could be administered [27].…”

“…The LD 50 and ED 50 of venom and antivenin of Mesobuthus species in mice are 0.18 mg/kg and 2.82 mg/kg respectively. High doses of venom and antivenin cause death and hypersensitivity reactions [26]. Therefore, there is need to reassess treatment of Mesobuthus tamulus envenomation in children.…”

“…Therefore, there is need to reassess treatment of Mesobuthus tamulus envenomation in children. The formula developed by Saganuwan [26] [25] indicating that the initial dose of the antivenin should be 30 mg (3 ml) followed by 60 mg (6 ml) of the second dose. The second dose should be 24 mg (2.4 ml).…”

“…The toxicity effect of scorpion is much higher than that of honeybee whose toxicity depends on the number of stings; hence death may be delayed giving rise to lethality time that has exponent (0.33). Median lethal time (LT 50 )isLD 50 over D p whereas D (dose) and P (exponent) are integral parts of the formula [26,34,35].…”

“…Lethal dose of snake venom could be neutralized by antidote equal to one-third of lethal dose with reference to body weight of the affected animal and safety of 10 À4 [35]. Treatment of scorpion envenomation requires antivenom that is 66.6% of median lethal dose of scorpion venom [26]. In both cases treatments shall continue until the patients recover from the toxicity.…”