Enteral Nimodipine is the standard of care in patients with SAH. Due to its calcium-channel-blocker activity, it is assumed to prevent vasospasm and to have a vasodilatory effects on cerebral vessels. But, six major studies 1-6 over the span of 15 years failed to provide a convincing evidence that nimodipine decreases the incidence of either angiographic or symptomatic vasospasm. Despite that, Nimodipine has shown to improve outcomes in SAH in multiple studies 5-7. Various alternative explanations have been put forward for its mechanism of action including
- reduction of calcium-dependent excitotoxicity
- decrease platelet aggregation
- dilation of small arteries not visible on angiograms
- inhibition of ischemia triggered by red blood cell products
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