The aims of the present open, non-comparative survey were to study the safety and efficacy of iopentol (Imagopaque, Nycomed Imaging AS, Oslo, Norway) in a large patient group. In a series of German centres, 3,587 patients underwent various contrast-enhanced examinations with iopentol. The most frequent examinations were computed tomography (CT) (1,740), phlebography (462), and digital subtraction angiography (DSA) (493). Only 82 patients (2.3%) experienced one or more adverse events. Sixty-one (1.7%) of these events were possibly or probably caused by the contrast medium. A total of 111 adverse events were registered, 54 of mild, 42 of moderate and 12 of strong intensity, and 51 events required treatment. The most frequent adverse events were nausea (34), erythema (14) urticaria (9), taste sensation (6), circulatory reactions (5) and angina pectoris (5). The frequencies of adverse events were 2.9% in CT, 2.0% in DSA, 2.0% in phlebography, 1.6% in cardioangiography, and 0.4% in urography. Patients with arteriosclerosis, an earlier contrast medium reaction, multimorbidity or age over 70 years had a statistically significantly higher risk of experiencing an adverse event. Patient tolerance was very good; the mean score was 83% on a visual analogue scale (VAS) ranging from extremely bad (0%) to extremely good (100%). Efficacy, as measured on VAS, was determined. Technical quality was scored as 80%, contrast enhancement within the vessels as 80% and delineation of lesions as 79%. The results from this large patient population confirms the experience from clinical practice that iopentol is a safe, well tolerated and efficient contrast medium.