One hundred and fifty-nine previously untreated patients with small cell lung cancer (SCLC), who were not eligible for intensive chemotherapy, were entered into a randomised study of intravenous (i.v.) doxorubicin and ifosfamide (with mesna) and oral etoposide. The i.v. drugs were given either by bolus therapy or by a continuous infusion (CI) pump over 7 days via a central venous line. Therapy was given for 6 weeks only. On weeks 1, 3 and 5 IV doxorubicin 35 mg m-2 was given with 5 days of oral etoposide 100 mg m-2 daily. On weeks 2, 4 and 6 IV ifosfamide 5 g m-2 was given with equidose mesna. The overall median survival was 25 weeks for patients in the bolus arm and 30 weeks for the CI therapy (P = 0.45). The overall response rate was 64% (18% complete response-CR) and 69% (30% CR) respectively (P = 0.13). The median WHO score for haematological toxicity was 4 for bolus therapy and 3 for CI therapy (P = 0.0007). Despite a trend for less supportive care for patients on CI therapy there were no significant differences in the use of i.v. antibodies and blood or platelet transfusions. There were fewer treatment delays due to myelotoxicity in the CI arm (P = 0.04). The median WHO score for non-haematological toxicity was 2 in both treatment groups. There was significantly less nausea (P = 0.037) but more mucositis (P = 0.01) in the CI arm. Weekly chemotherapy using CI treatment was as effective as bolus therapy. It was well accepted by patients. The assessment of quality of life in a subgroup of patients showed a statistically significant reduction in anxiety and depression for both groups of patients during therapy.