Background. A previous single dose placebo-controlled double-blinded trial showed an extremely low (0.4%) intolerance rate of sodium ferric gluconate complex (SFGC) in SFGC-naive haemodialysis patients. No large prospective trials have assessed the safety of SFGC during repeated exposure in the outpatient haemodialysis setting. Methods. Chronic haemodialysis patients completing the single-dose trial of SFGC were eligible to participate in this prospective, multicentre, open-label, long-term evaluation of SFGC, designed to record adverse events occurring up to 72 h post-dose. Patients received as many as 20 ampules (1250mg total) of SFGC at an investigator-determined dose and rate over a 9 month evaluation period. Results. Among 1412 enrolled patients at 54 centres, 1321 received 13 151 infusions of SFGC. Most doses (94.8%) were ≤125 mg and the majority were given over 10 min. Infusion rates ranged from <5 to 125 mg/min. There were no life-threatening events. Fifty-one patients (3.9%) experienced an adverse event, possibly related to SFGC. Of these, one experienced a serious event (hypotension). Five patients (0.4%) experienced an event that precluded SFGC readministration: pruritus (three), vasodilatation (one) and loss of taste (one). Among 372 patients (28.2%) receiving angiotensin-converting enzyme inhibitor (ACEI) therapy, adverse events were neither more common nor more severe than in the other patients. Conclusions. Repeated doses of SFGC are very well tolerated in haemodialysis patients. No life-threatening events were observed in over 13 000 doses administered. Administration of SFGC to patients using ACEI is safe and does not increase the incidence or severity of adverse events to SFGC. © ERA-EDTA 2004; all rights reserved.