Abstract
An analysis of the recent trials on the effect of nimodipine on the prevention of delayed ischaemic deficits (DID) due to vasospasm provides strong evidence that the drug reduces the incidence and the severity of DID. Placebo-controlled prospective randomized studies with oral administration of nimodipine prove that patients treated with nimodipine suffer severe disabihty or death due to vasospasm less frequently than those not treated. Non-controlled open prospective trials with early surgery and intravenous and oral nimodipine present the lowest pubhshed incidence of DID in aneurysmal subarachnoid haemorrhage.