The new algorithm for calculation of median lethal dose (LD50) and effective dose fifty (ED50) of Micrarus fulvius venom and anti-venom in mice

One million people throughout the world are bitten yearly by poisonous snakes. Of this, one-tenth died and three-tenth suffer some forms of disabilities. In view of this, anti-snake venoms are currently being developed against viper and colubrid Snake Venoms using mice. Therefore, a new algorithm for calculation of median lethal dose (LD₅₀) and effective dose fifty (ED₅₀) was developed for Micrarus fulvius venom and antivenom respectively. This paper compared the formula of effective dose fifty (ED₅₀) developed by Spearman and Karber with ideal median lethal dose (IMLD₅₀) formula developed by Saganuwan with a view to bringing out their difference and similarity in calculation of ED₅₀ that could be used to develop a new median lethal dose formula for calculation of Micrarus fulvius venom in mice. The findings revealed that ED₅₀ value (477 mg/kg) from Spearman and Karber's formula ( ${\text{ED}}_{50}=\log {\text{ED}}_{50}=\log X_{100}-\frac{\log \text{FD}}{n}(\Sigma t-n/2)$ is comparatively similar with ideal median lethal dose value (428.75 mg/kg) from Saganuwan's formula (MLD₅₀ + MSD₅₀/2). The new LD₅₀ formula ( ${\text{LD}}_{50}=\left(\frac{{\mathrm{ED}}_{50}}{3}\right)\times \text{Wm}\times {10}^{-4}$ ) yielded value (0.29 mg/kg) of comparative significance with reported value (0.32 mg/kg). When ED₅₀ is equal to 2LD₅₀, the denominator of $\frac{{\text{ED}}_{50}}{3}$ becomes 2. In conclusion, the new formula would yield low doses of snake anti-venoms with reduced possibility of hypersensitivity reaction.

Effective dose; Median lethal dose; Mice; Micrarus fulvius; Snake anti venom; Snake venom.