Sixty-six patients with portal hypertension and esophageal varices due to liver cirrhosis were randomized to receive either 5% ethanolamine oleate (EO) or 5% EO plus 1% polidocanol (EOP) as a sclerosant for endoscopic injection sclerotherapy (EIS). The two groups were well matched with regard to age, sex and the severity of liver disease. In no patient in the two groups was there any major complication, such as esophageal perforation or esophageal bleeding. Eradication of esophageal varices was attained with an average of 4.7 and 4.3 sessions of endoscopic injection sclerotherapy in the ethanolamine oleate and polidocanol groups, respectively. Data on one patient in the ethanolamine oleate group had to be excluded because he left the hospital after 2 sessions of endoscopic injection sclerotherapy. Esophageal ulcers occurred earlier in the polidocanol group (after an average of 2.8 weeks) than in the ethanolamine oleate group (3.8 weeks), the difference being statistically significant (P < 0.01). The rate of occurrence of esophageal stricture requiring more than 2 sessions of bougienage was significantly (P < 0.01) higher in the polidocanol group (16/33, 48%) than in the ethanolamine oleate group (4/32, 12%). This study suggests that the two sclerosants have equal efficacy for treating patients with esophageal varices. With polidocanol there was ulceration and stricture in the distal esophagus.