Strategies for Pharmacological Intervention

Abstract

Nimodipine is a 1,4-dihydropyridine (DHP) calcium channel blocker, which is used in the treatment of neurological deficits, associated with subarachnoid haemorrhage. Nimodipine is a highly lipid-soluble dihydropyridine derivative that readily crosses the blood-brain barrier. In animal studies, nimodipine has been shown to be effective in increasing cerebral blood flow; preventing vasoconstriction attributable to sympathetic stimulation, hypocapnia, and hypertension; and improving neurological outcome after cerebral ischaemia. Nimodipine is reported to be 90% protein bound; its half-life is approximately 13 h, with substantial interpatient variability. Nimodipine has been studied in the prevention and treatment of cerebral arterial spasm in patients with subarachnoid haemorrhage. In four open trials, in which nimodipine was administered orally, intravenously, topically during surgery, or by intracarotid injection, and in two double-blind, placebo-controlled trials, neurological outcomes were improved in patients receiving the drug. However, in both sets of trials nimodipine had limited effects on cerebral arterial spasm. Although nimodipine can cause hypotension, no serious adverse reactions to the drug were reported in clinical trials in patients with subarachnoid haemorrhage. Based on the data currently available, nimodipine appears to improve neurological outcome in patients with subarachnoid haemorrhage.