Background Hematoma enlargement occurs in up to two third of acute intracerebral hemorrhage (AICH) patients within 24 hours from onset.Expanding hematoma is often accompanied by the severe morbidity and mortality.Herbal medicine of promoting blood circulation (PBC) and resolving blood stasis (RBS) were often medicated to treating AICH in China, though safety data about hematoma enlargement were rarely reported.