NIMOTOP
Clinical safety rating: caution
Comprehensive clinical and safety monograph for NIMOTOP (NIMOTOP).
Nimodipine is a dihydropyridine calcium channel blocker that selectively inhibits calcium influx into vascular smooth muscle cells, leading to vasodilation. It has a preferential effect on cerebral arteries, reducing the incidence of vasospasm following subarachnoid hemorrhage.
| Metabolism | Nimodipine is extensively metabolized in the liver primarily by the CYP3A4 isoenzyme, with no significant first-pass effect. Metabolites are excreted mainly in bile (about 80%) and urine (about 20%). |
| Excretion | Primarily hepatic metabolism; 50% excreted in urine as metabolites, 30% in feces via biliary elimination. Less than 1% excreted unchanged in urine. |
| Half-life | Terminal elimination half-life is approximately 8–9 hours (range 3–12 hours) in adults, with clinical context of twice-daily dosing for continuous cerebral vasodilation in subarachnoid hemorrhage. |
| Protein binding | 97–99% bound to plasma proteins, primarily albumin and alpha-1-acid glycoprotein. |
| Volume of Distribution | Volume of distribution is 0.9–1.6 L/kg (average 1.2 L/kg), indicating extensive tissue distribution and high lipophilicity. |
| Bioavailability | Oral: 13% (range 3–30%) due to extensive first-pass metabolism. Intravenous: 100%. |
| Onset of Action | Oral: 1–3 hours. Intravenous: within minutes, with peak effect at 1 hour after infusion initiation. |
| Duration of Action | Oral: 12–24 hours with twice-daily dosing. Intravenous: 4–8 hours post-infusion; clinical effect may persist longer due to cerebrovascular selectivity. |
60 mg orally every 4 hours for 21 days, initiated within 96 hours of subarachnoid hemorrhage. If unable to swallow, 0.5 mg/h continuous IV infusion via central line; increase to 1 mg/h after 2 hours if tolerated, continue for up to 21 days.
| Dosage form | CAPSULE |
| Renal impairment | No dose adjustment required for renal impairment. Use caution in severe renal failure due to risk of accumulation of metabolites. |
| Liver impairment | Contraindicated in severe hepatic impairment (Child-Pugh C). In mild to moderate (Child-Pugh A or B), reduce oral dose to 30 mg every 4 hours or decrease IV infusion rate to 0.5 mg/h; monitor blood pressure closely. |
| Pediatric use | Safety and efficacy not established in pediatric patients; no recommended dosing. |
| Geriatric use | No specific dose adjustment required, but elderly patients may be more sensitive to hypotensive effects; monitor blood pressure closely and consider starting at lower end of dosing range. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for NIMOTOP (NIMOTOP).
| Breastfeeding | Excreted in breast milk; M/P ratio unknown. Use with caution; monitor infant for hypotension and bradycardia. |
| Teratogenic Risk | Teratogenicity not established in humans; animal studies show no fetal harm. Use only if maternal benefit outweighs risk. First trimester: avoid unless essential. Second/third trimesters: potential for maternal hypotension and reduced uteroplacental perfusion. |
| Fetal Monitoring |
■ FDA Black Box Warning
No FDA black box warning.
| Serious Effects |
["Hypersensitivity to nimodipine or any component of the formulation","Concomitant use with strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, clarithromycin) or inducers (e.g., rifampin, phenytoin, carbamazepine)"]
| Precautions | ["Hypotension: May cause systemic hypotension, especially in patients with compromised cardiovascular function","Hepatic impairment: Reduce dose in patients with liver cirrhosis due to increased bioavailability","Intestinal pseudo-obstruction: Rare cases reported; monitor for decreased bowel sounds or abdominal distension"] |
Loading safety data…
| Monitor maternal blood pressure, heart rate, and neurologic status. Fetal heart rate monitoring and ultrasound for growth and placental perfusion. |
| Fertility Effects | No evidence of impaired fertility in animal studies. Human data lacking. |