A Cochrane review included 16 studies with a total of 3 361 subjects. Three of the studies were of magnesium sulphate in addition to nimodipine. Overall, calcium antagonists reduced the risk of poor outcome defined as death or dependency in activities of daily life (RR 0.81, 95% CI 0.72 to 0.92; 9 studies, n= 2 589); the corresponding number of patients needed to treat was 19 (95% CI 1 to 51). For oral nimodipine alone the RR was 0.67 (95% CI 0.55 to 0.81, 4 studies, n=853), for other calcium antagonists (nicardipine and AT877) or intravenous administration of nimodipine the results were not statistically significant. Calcium antagonists reduced the occurrence of secondary ischaemia (RR 0.66, 95% CI 0.59 to 0.75; 11 studies, n=2 303) and showed a favourable trend for case fatality (RR 0.87, 95% CI 0.73 to 1.02; 11 studies, n=2 775). For magnesium in addition to standard treatment with nimodipine (3 studies, n=379), the RR was 0.75 (95% CI 0.57 to 1.00) for a poor outcome and 0.66 (95% CI 0.45 to 0.96) for clinical signs of secondary ischaemia.
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