Blood ammonia nitrogen was determined in 36 cases of hepatic coma and 63 cases of liver disease. Significant elevations (PL 0.001) were noted in coma due to hepatitis and cirrhosis and the mortality rate was 89% and 9 1.3% respectively. Raised ammonia nitrogen in hepatic coma is a sign of grave prognosis (JPMA 34 : 9, 1984).