Nimotop 30 mg Tablets

Brand Name

The medication is commercially distributed under the trade name Nimotop, a designation well-established in the realm of neurological and vascular therapies. This branding underscores its specialized role in addressing critical conditions related to cerebral circulation.

International Non-Proprietary Name (INN)

Nimotop is universally identified by its international non-proprietary name, nimodipine. This term reflects the active pharmacological entity at its core, ensuring its recognition remains uniform across global healthcare systems and scientific literature.

Form of Release

This drug is available in two primary forms: film-coated tablets and an intravenous infusion solution. Tablets are typically supplied in 30 mg doses, while the infusion solution is provided in 10 mg/50 mL vials, designed for controlled administration in acute settings. Both formulations cater to distinct therapeutic needs, offering flexibility in treatment approaches.

Composition

The key active component in Nimotop is nimodipine, a dihydropyridine calcium channel blocker with selective effects on cerebral vessels. In tablets, it is combined with excipients such as microcrystalline cellulose, corn starch, povidone, magnesium stearate, and a coating of hypromellose, polyethylene glycol, and titanium dioxide for stability and appearance. The infusion solution includes ethanol, macrogol, sodium citrate, citric acid, and water for injection, formulated to ensure solubility and safe delivery through intravenous routes.

Pharmacologic Properties

Pharmacodynamics

Nimotop functions by selectively blocking calcium entry through L-type channels in vascular smooth muscle, with a pronounced affinity for cerebral arteries. This action promotes vasodilation, enhancing blood flow to brain tissues while minimizing systemic pressure changes. By preventing calcium overload in neurons, it also offers protective effects against ischemic damage, particularly following vascular disruptions. These properties make it a valuable agent in mitigating spasms and preserving neurological function under stress.

Pharmacokinetics

After oral intake, nimodipine in Nimotop is absorbed rapidly from the gastrointestinal tract, though bioavailability is low, around 13%, due to extensive first-pass metabolism. Peak plasma levels occur within 0.5 to 1.5 hours for tablets, or immediately with infusion. It distributes widely, crossing the blood-brain barrier effectively, with a volume of distribution near 0.9-1.7 L/kg, and binds extensively to plasma proteins at over 95%. Hepatic metabolism via cytochrome P450 3A4 yields inactive metabolites, excreted primarily in urine (50%) and feces (32%). The elimination half-life ranges from 1 to 2 hours, though its effects persist longer due to tissue affinity.

Indications for Use

Diseases and Conditions

Nimotop is prescribed to prevent and treat neurological deficits resulting from cerebral vasospasm following subarachnoid hemorrhage, often linked to aneurysm rupture. It aims to reduce the incidence and severity of ischemic complications by maintaining adequate cerebral perfusion during this critical period. The intravenous form is typically used in acute hospital settings, while tablets support ongoing management, reflecting its targeted role in neurosurgical care.

Contraindications

Conditions Prohibiting Use

Nimotop must not be given to patients with a known allergy to nimodipine or any formulation component, as reactions could span mild irritation to severe hypersensitivity syndromes. It is inappropriate for individuals with significant hypotension or unstable hemodynamics, where further vessel relaxation might compromise vital organ perfusion. Use is also restricted in cases of severe liver dysfunction, particularly cirrhosis with portal hypertension, due to impaired metabolism amplifying drug exposure. Concurrent administration with strong CYP3A4 inducers, like rifampicin, is contraindicated, as it drastically reduces efficacy.

Method of Administration and Dosage

Administration Guidelines

Nimotop tablets are taken orally, preferably on an empty stomach, at least one hour before or two hours after meals, to optimize absorption. They should be swallowed whole with water, avoiding grapefruit juice, which can elevate drug levels. The intravenous solution is administered via a central line or large peripheral vein using a pump, protected from light, and often co-infused with compatible fluids like saline or dextrose, never mixed directly with other drugs.

Dosage for Adults and Children

For adults post-subarachnoid hemorrhage, Nimotop infusion begins at 1 mg/hour (5 mL/hour) for the first two hours, increasing to 2 mg/hour (10 mL/hour) if tolerated, continued for 5-14 days. Oral dosing follows at 60 mg every 4 hours (360 mg daily) for 21 days total, starting within 96 hours of the event. Pediatric use lacks established guidelines; when deemed necessary, dosing is extrapolated cautiously from adult regimens, typically reduced proportionally by weight, under specialist oversight due to limited evidence.

Dose Adjustment in Specific Conditions

Renal impairment generally requires no dose change, as excretion is not heavily kidney-dependent, though monitoring for hypotension is advised in severe cases. Hepatic dysfunction, especially moderate to severe, demands lower doses—infusion may drop to 0.5 mg/hour initially, and oral doses might decrease to 30 mg every 4 hours—due to prolonged clearance and heightened effect intensity. Elderly patients follow standard dosing unless organ function declines significantly, warranting similar adjustments.

Side Effects

Potential Adverse Reactions

Nimotop may trigger various unintended effects, most frequently mild hypotension, manifesting as dizziness or lightheadedness, especially during infusion. Headaches, flushing, or warmth are common, reflecting its vasodilatory action, while nausea, abdominal discomfort, or diarrhea occasionally arise. Heart rate changes, either slowing or quickening, have been observed, as have rare instances of rash or sweating. Neurological symptoms like tremor or fatigue may occur, typically resolving with time or dose tweaking, though persistent issues merit medical consultation.

Overdose

Symptoms of Overdose

An overdose of Nimotop can precipitate excessive vasodilation, leading to profound hypotension with symptoms like fainting, weakness, or confusion. Rapid heartbeat or irregular rhythms may accompany this, alongside gastrointestinal distress such as vomiting or severe cramps. In extreme cases, respiratory difficulty or neurological impairment might signal critical escalation, necessitating swift response to avert systemic collapse.

First Aid Measures

Upon overdose, stop Nimotop administration immediately and position the patient supine with legs raised to bolster circulation. Urgent medical care is essential, with intravenous fluids or vasopressors like norepinephrine used to restore blood pressure. Monitoring cardiac and respiratory function guides further intervention, while avoiding additional doses until fully stabilized prevents worsening of the condition.

Drug Interactions

Effects on Other Medications

Nimotop’s metabolism via CYP3A4 creates significant interaction potential. Strong inhibitors like ketoconazole, itraconazole, or ritonavir can raise nimodipine levels, intensifying hypotension risks, while inducers such as phenytoin or carbamazepine diminish its effectiveness, often requiring alternative therapies. It may enhance the hypotensive effects of other antihypertensives or vasodilators, necessitating careful titration. No notable impact on other drugs’ metabolism occurs, as it does not significantly alter enzyme activity itself.

Compatibility with Alcohol and Food

Alcohol use with Nimotop can amplify vasodilation, increasing dizziness or pressure drops, and should be avoided. Grapefruit juice inhibits CYP3A4, elevating drug concentrations, and is contraindicated within hours of dosing. Other foods have minimal impact, though consistent intake patterns support stable absorption and effect predictability.

Special Precautions

Use During Pregnancy and Breastfeeding

Nimotop use in pregnancy lacks comprehensive safety data; animal studies suggest possible fetal risks, so it is reserved for cases where maternal benefit outweighs uncertainty, with close monitoring. Nimodipine appears in breast milk in trace amounts; while no adverse infant effects are confirmed, breastfeeding mothers should weigh risks with providers, potentially pausing lactation during critical treatment phases.

Impact on Driving and Operating Machinery

Nimotop may cause dizziness or fatigue, particularly early in therapy or during infusion, potentially impairing driving or machinery operation. Patients should gauge their reaction before such activities, abstaining if symptoms interfere, to maintain safety until accustomed to its effects.

Considerations for Elderly and Pediatric Populations

Elderly patients may tolerate Nimotop well at standard doses but face higher hypotension risks with age-related vascular changes, often needing blood pressure checks during initiation. Pediatric application is rare and unstandardized, used only in exceptional neurological cases with reduced, carefully monitored doses due to scarce safety data. Both groups require tailored management to ensure efficacy without undue risk.