Albino rats were pretreated orally for seven days with different doses of the essential oil and juice of garlic. These animals were challenged with isoprenaline (85 mg/kg, s.c.) on day six and seven to induce myocardial necrosis. The same rats were also subjected to swimming test before and after forty eight hr of first injection of isoprenaline. Pretreatment with essential oil (2.0 and 4.0 mg/kg) and juice (2.0 and 4.0 ml/kg) significantly protected the myocardium from isoprenaline-induced necrosis. These animals also exhibited better swimming performance. In separate group of animals, pretreatment with garlic juice (4.0 ml/kg) or essential oil (4.0 mg/kg) improved the chances of survival in isoprenaline-challenged animals.