Influence of coca chewing on hematological and cardiorespiratory responses to submaximal exercise

Abstract

Summary. The cardiovascular effects of cocaine are relatively well known but little information is available concerning those of coca chewing. The present study was undertaken to determine the hematological and cardiovascular status, at rest and during prolonged (1 hr.) submaximal exercise in a group (n = 12) of chronic coca users after chewing 50 grams of coca leaves. The results were compared to those obtained in a group (n = 12) of non chewers. At rest, coca chewing was accompanied by a significant increase in heart rate, hematocrit, hemoglobin concentration, and plasma norepinephrine level. In addition, we found that coca chewing for 1 hr. resulted in a significant decrease in blood and plasma a volume. During submaximal exercise, coca chewers displayed a significantly higher heart rate and mean arterial blood pressure. The exercise-induced hemoconcentration was similar in coca chewers and non-chewers. It is concluded that 1/ the coca-induced fluid shift observed in resting conditions in coca chewers are cumulative to that of exercise, and 2/ coca chewing prior to exercise increases heart rate and blood pressure. These changes in normal hematological and cardiovascular functions could no only exercise tolerance, but more important, could be potentially dangerous.