BACKGROUND Hemorrhage volume is an important predictor of outcome in patients with intracerebral hemorrhage (ICH). It is not clear why in some patients ICH volume is larger than in others. Identification of modifiable factors responsible for large-volume hemorrhage in hypertensive patients may help to reduce ICH-related morbidity and mortality. OBJECTIVE The objective of this study was to identify predictors of large-volume ICH in hypertensive patients. METHODS At a tertiary care center in Karachi (Pakistan), 157 hypertensive patients with ICH were prospectively analyzed in 2008-2009, and hemorrhage volumes were determined using CT or MRI and various factors, including duration of hypertension, medical treatment, compliance, co-morbidity, and hematologic and coagulation profiles. Logistic regression analysis was used to identify predictors of high-volume hemorrhage. A volume >30 mm(3) was defined as high-volume hemorrhage. RESULTS Of 157 patients with hypertensive ICH evaluated, 133 patients were included in the study, and 24 patients with brain stem, cerebellum and pure intraventricular hemorrhage were excluded. The mean age of the study patients was 55 years; 56 patients (70%) were male. High-volume hemorrhage (>30 mm(3)) was noted in 47 (35%) patients. Mortality was significantly increased in patients with high-volume ICH (32 vs. 6% in patients with low-volume ICH). In univariate analysis, factors significantly associated with large-volume ICH were male gender (p = 0.002), hypertension lasting >10 years (p = 0.03), warfarin treatment (p = 0.05), use of >1 anti-hypertensive agent (p = 0.001) and poor compliance with medication (p = 0.001). In multivariate analysis, use of >1 anti-hypertensive agent and poor compliance were also predictors of large-volume ICH. CONCLUSION High-volume hemorrhage was less common (28%) in our patients with hypertension and ICH. Use of >1 anti-hypertensive agent and poor compliance were predictors of large-volume ICH.