The effect of magnesium sulfate in treatment of experimental oleander (Nerium oleander) poisoning in sheep

The purpose of this study was evaluation of magnesium sulfate effect in treatment of acuteoleander intoxication in sheep. Eleven young native sheep randomly divided into 2 groups, 6sheep being allocated to the treatment group and 5 served as controls. Sheep of both groups weredosed with a lethal dose of 110mg/kg body weight of dried oleander leaves. In sheep of treatmentgroup, following development of ventricular arrhythmias, magnesium sulfate was slowlyadministered intravenously with dose rate of 100mg/kg body weight. Clinical signs of toxicosiswere developed within 30 -40 minutes after dosing of the plant. Serial electrocardiographyrevealed various abnormalities and arrhythmias of cardiac rhythm in sheep of control group.Animals of control group died within 4.5 to 12 hours (median 8.5 hours) after receiving the toxicmaterial. Administration of magnesium sulfate in sheep of treatment group suppressedventricular arrhythmias to benign ones or normal sinus rhythm but its effect was transient andpersisted for 3 to 3.5 hours. Second injection of magnesium had same effect but there was noconsiderable therapeutic effect after third injection of the drug. Sheep of treatment group diedwithin 18 to 34 hours (median 24.5 hours) after receiving the oleander. Statistical analysisrevealed a highly significant difference in survival time between the control and the treatmentgroups (p<0.004). The results suggested that magnesium sulfate can be used as a complementarytherapeutic agent for treatment of acute oleander toxicosis in farm animals.