To specify immunological and pathogenetic aspects of imunophan use in aged patients with duodenal ulcer (DU). Imunophan was given to 24 DU patients (mean age 62.0 +/- 1.5 years), in whom the size of ulcer varied from 0.6 to 2.1 cm. The patients on anti-ulcer therapy plus imunophan had a pain relief median 6.2 +/- 0.2 days (p < 0.001), control ones--11.8 +/- 0.1 days. The median of scarring duration in the test group was 16.2 +/- 0.2 days (p < 0.001), in the controls--23.8 +/- 0.3 days. In 3 (30.0%) cases the scars were rough. The count of T-lymphocytes in the study group increased from 53.1 +/- 0.6 to 65.1 +/- 0.2% (p < 0.001), of T-helpers/inductors--from 27.8 +/- 0.2 to 38.5 +/- 0.3% (p < 0.001), of cytotoxic T-lymphocytes--from 18.5 +/- 0.5 to 27.3 +/- 0.3 (p < 0.001), of B-lymphocytes--from 12.3 +/- 0.2 to 19.1 +/- 0.1% (p < 0.001). The therapy including imunophan reduced concentration of malonic dialdehide by 23.5%, trienic conjugates by 61.6%; raised the level of superoxide dismutase 1.6-fold, catalase 1.4-fold, glutathione reductase by 41.9% (p < 0.001). Neither immune status nor LPO-AOD changed significantly in patients on the basic therapy alone. The results obtained evidence for a positive action of imunophan on inflammation, immune status and antioxidant defense. Therefore, imunophan can be recommended as an adjuvant of basic anti-ulcer therapy in elderly and senile patients.