Tab%2520nimodipine

#Tab%2520nimodipine ## Overview Nimodipine is a dihydropyridine calcium channel blocker with high lipophilicity, allowing it to cross the blood-brain barrier. It preferentially dilates cerebral arterioles. Available as oral capsules (30 mg). No injectable formulation in many regions; oral route is standard for prophylaxis. ## Primary Indications - **Prophylaxis and treatment of cerebral vasospasm** following aneurysmal subarachnoid hemorrhage (aSAH). Used to reduce incidence and severity of ischemic deficits. ## Adult Dosing - **Standard dose:** 60 mg (two 30 mg capsules) every 4 hours for 21 consecutive days. - **Start within 96 hours** of subarachnoid hemorrhage. - **If unable to swallow** capsules whole, contents can be extracted via syringe (using an oral dosing syringe) and administered via nasogastric tube; rinse tube with normal saline. - **Maximum daily dose:** 360 mg (60 mg × 6 doses). ## Pediatric Dosing - **Not FDA-approved for children.** Limited data; no established routine dosing. - Off-label use in pediatric aSAH has been reported at 0.5–1 mg/kg orally every 4 hours, but local protocol must be followed. Consultation with pediatric neurology/neurosurgery is strongly recommended. ## Dose Adjustments - **Hepatic impairment (cirrhosis):** Reduce dose to 30 mg every 4 hours. Monitor blood pressure and dose interval may need adjustment. - **Renal impairment:** No specific dose adjustment required, but use caution in severe impairment (creatinine clearance <30 mL/min). - **Elderly:** Lower initial doses may be considered due to increased sensitivity to hypotension. ## Contraindications - Known hypersensitivity to nimodipine or any dihydropyridine. - **Do not administer with** grapefruit juice (increases drug levels). - **Not for intravenous use** (different formulation has different safety profile; oral only for this product). ## Adverse Effects - **Common:** Hypotension (dose-related), headache, peripheral edema, dizziness, flushing. - **Serious:** Bradycardia, ileus (especially in aSAH patients), hepatitis, thrombocytopenia (rare). - **Decreased blood pressure** may reduce cerebral perfusion; monitor carefully. ## Key Drug Interactions - **Antihypertensives** (especially beta-blockers): additive hypotension. - **CYP3A4 inhibitors** (e.g., clarithromycin, ketoconazole, ritonavir): increase nimodipine levels – avoid combination or reduce dose. - **CYP3A4 inducers** (e.g., carbamazepine, phenytoin, rifampin): decrease nimodipine levels – consider alternative or monitor efficacy. - **Grapefruit juice:** avoid entirely. ## Monitoring - **Blood pressure and heart rate** before each dose (hold if systolic BP <90 mmHg or significant symptomatic hypotension). - **Neurological status** for signs of vasospasm (e.g., new focal deficits, altered consciousness). - **Liver function tests** if prolonged therapy or hepatic comorbidities. - **Electrolytes and renal function** as part of standard aSAH care. ## Clinical Pearls - Nimodipine does **not** treat vasospasm after it occurs; it is used prophylactically to reduce incidence. - Administer consistently every 4 hours – timing is critical for steady-state levels. - Capsules must be swallowed whole or mixed with a small amount of apple juice/syrup if giving via NG tube; do not crush. - **Photosensitivity** precautions: avoid excessive sunlight exposure. - Most common reason for discontinuation is hypotension; temporary dose reduction or support with fluids/vasopressors may be needed. --- *This information is for educational purposes and does not replace clinical judgment. Always verify current prescribing information, local protocols, and formulary availability before administration.*