Tab Nimodipine

## Overview Nimodipine is a calcium channel blocker with a higher affinity for cerebral arteries compared to peripheral arteries. It is primarily used to prevent cerebral vasospasm following subarachnoid hemorrhage (SAH). ## Primary Indications * Prevention of cerebral vasospasm and subsequent ischemic neurologic deficits in patients who have experienced a subarachnoid hemorrhage (SAH). ## Adult Dosing * **Oral:** 60 mg every 4 hours for 21 days. * Dosing may begin as soon as possible, preferably within 72 hours of SAH. * If oral administration is not feasible, a nasogastric tube may be used. The capsules should be pierced and the contents administered via NG tube. Do not administer the capsule contents directly into the NG tube without dilution. * **Intravenous (IV) administration of oral nimodipine solution is NOT recommended due to risk of fatal overdose. Specifically formulated IV nimodipine is available in some regions but is not widely available.** ## Pediatric Dosing * Pediatric dosing for nimodipine is not established. Use in pediatric patients is generally not recommended. ## Dose Adjustments * No specific dose adjustments are routinely recommended for hepatic or renal impairment. However, caution and close monitoring are advised, particularly in patients with severe hepatic dysfunction, as metabolism may be reduced. ## Contraindications * Hypersensitivity to nimodipine or any component of the formulation. * Concurrent use with strong CYP3A4 inhibitors (e.g., ritonavir). ## Adverse Effects * **Common:** Hypotension, headache, nausea, gastrointestinal upset. * **Less Common:** Dizziness, flushing, edema, rash, elevated liver enzymes. * **Serious:** Severe hypotension, myocardial infarction, heart failure. ## Key Drug Interactions * **CYP3A4 Inhibitors:** Concurrent use with strong CYP3A4 inhibitors (e.g., ritonavir, ketoconazole, itraconazole, grapefruit juice) can significantly increase nimodipine plasma concentrations, leading to potential toxicity. Avoid coadministration. * **CYP3A4 Inducers:** Concurrent use with CYP3A4 inducers (e.g., rifampin, carbamazepine, phenytoin, phenobarbital) can decrease nimodipine plasma concentrations, potentially reducing efficacy. * **Antihypertensives:** Additive hypotensive effects may occur when used concurrently with other antihypertensive agents. ## Monitoring * **Blood Pressure:** Monitor blood pressure regularly, especially during initiation of therapy and dose adjustments, and particularly if administered concurrently with other antihypertensives. * **Neurological Status:** Assess neurological status for any signs of recurrent vasospasm or neurological deficit. * **Liver Function Tests:** Monitor liver function periodically, especially in patients with pre-existing liver disease. ## Clinical Pearls * Nimodipine's efficacy is primarily in preventing the *consequences* of vasospasm, not in directly reversing existing vasospasm. * The oral formulation is the standard of care for SAH outside of specific IV formulations. * Careful administration is crucial for the oral suspension via NG tube to avoid overdose. *** **Disclaimer:** This information is intended for clinical use and does not substitute for professional medical advice. Always consult the most current prescribing information and institutional protocols before making any treatment decisions.