Antiaggregation effect of alum on human platelets

OBJECTIVE: The purpose of this study was to evaluate the effect of alum on human platelet aggregation. METHODS: Platelet-rich plasma fractions were prepared from fresh blood drawn from a group of healthy male volunteers. Platelet aggregation was induced by various inducers. The percent aggregation was recorded in the absence and presence of various concentrations of alum. RESULTS: Alum at concentrations less than 1.5 mg/ml inhibited platelet aggregation induced by collagen, epinephrine. ADP and thrombin in a dose-dependent manner. The IC50s were 0.668, 0.324, 0.250 and 0.191 mg/ml of alum, for collagen-, epinephrine-, ADP- and thrombin-induced platelet aggregation, respectively. In contrast, alum at concentrations up to 1.5 mg/ml did not inhibit ristocetin-induced platelet aggregation. CONCLUSION: Alum has an anti-platelet action and should be used cautiously in the treatment of intractable intravesical hemorrhage. Alum is a cheap anti-platelet drug that needs further investigation.