This is a non-randomized open assessment of eicosapentaenoic acid (EPA) supplementation in ten people (five males) with refractory focal seizures. Each received 1000mg of EPA daily for 3months. Six people had fewer seizures during the supplementation period compared with baseline (range 12 to 59% reduction) and one other person had markedly reduced seizure severity. The mean reduction in seizure frequency was 16% (95% CI — 10% to 35%, p=0.26). With the small number of participants and open nature of the study, interpretation of the results is difficult, but a possible weak effect of EPA on seizures cannot be discounted. Further examination of EPA supplementation should be undertaken with larger numbers of people in controlled trials. Higher doses and longer duration of treatment should be considered.