Tetanus, although a disease of third world but significant number of cases are reported every year in America and Europe.Annual world mortality from tetanus is estimated to be 800,000- 1000,000 making it a significant public health problem in developed countries.Tetanus is characterized by muscle spasms which leads to asphyxia and ultimately death if untreated. Conventional treatment is heavy sedation to avoid spasms along with other supportive measures. Heavy sedation leads to artificial ventilation.More than 60% mortality in tetanus occurs due to heavy sedation and artificial ventilation.Therefore there was continuous search to control spasms without the need for heavy sedation and artificial ventilation. Magnesium Sulphate is being used as anticonvulsant in eclampsia.Very few people have studied the effect of magnesium sulphate in tetanus. The purpose of this study was to determine the role of magnesium sulphate for control of muscle spasms in severe tetanus (grade 3 & 4) and minimize the need for sedation and artificial ventilation.