Nimodipine

Absorption

In humans, nimodipine is rapidly absorbed after oral administration, and peak concentrations are generally attained within one hour. Bioavailability is 100% following intravenous administration and 3-30% following oral administration due to extensive first-pass metabolism.

Toxicity

Symptoms of overdosage would be expected to be related to cardiovascular effects such as excessive peripheral vasodilation with marked systemic hypotension.

Description

Nimodipine is a cerebral vasodilating calcium antagonist related to nifedipine. It is indicated for the prophylaxis and treatment of neurological deficits due to cerebral vasospasm after subarachnoid hemorrhage.

Chemical properties

Crystalline Solid

Originator

Bayer (W. Germany)

The Uses of Nimodipine

Nimodipine has been used:

• as a L-type calcium channel (LTCC) inhibitor, to evaluate its neuroprotective activity in the vibrosections
• as a standard, in the enantioseparation of chiral drugs by high performance liquid chromatography (HPLC)
• in the pharmacological studies for the measurement of spine voltage escape

The Uses of Nimodipine

Used as a cerebral vasodilator. A dihydropyridine calcium channel blocker

The Uses of Nimodipine

A dihydropyridine calcium channel blocker. It is used as a vasodilator (cerebral).

The Uses of Nimodipine

provitamin, antixerophthalamic

Indications

For use as an adjunct to improve neurologic outcome following subarachnoid hemorrhage (SAH) from ruptured intracranial berry aneurysms by reducing the incidence and severity of ischemic deficits.

Background

Nimodipine is a 1,4-dihydropyridine calcium channel blocker. It acts primarily on vascular smooth muscle cells by stabilizing voltage-gated L-type calcium channels in their inactive conformation. By inhibiting the influx of calcium in smooth muscle cells, nimodipine prevents calcium-dependent smooth muscle contraction and subsequent vasoconstriction. Compared to other calcium channel blocking agents, nimodipine exhibits greater effects on cerebral circulation than on peripheral circulation. Nimodipine is used to as an adjunct to improve the neurologic outcome following subarachnoid hemorrhage from ruptured intracranial aneurysm.

What are the applications of Application

Nimodipine is an L-type calcium channel protein inhibitor

Definition

ChEBI: A dihydropyridine that is 1,4-dihydropyridine which is substituted by methyl groups at positions 2 and 6, a (2-methoxyethoxy)carbonyl group at position 3, a m-nitrophenyl group at position 4, and an isopropoxycarbonyl group at position 5. An L type calcium channel blocker, it acts particularly on cerebral circulation, and is used both orally and intravenously for the prevention and treatment of subarachnoid hemorrhage from ruptured intracranial aneurysm.

Manufacturing Process

After 8 hours boiling of solution of 3.8 g of 3'-nitro-benzylideneacetoacetic acid isopropylester, 8 grams of acetoacetic acid β-metoxyethyl ester and 6 ml conc ammonia in 80 ml ethanol under reflux, 2,6-dimethyl-4-(3'-nitrophenyl)- 1,4-dihydropyridine 3-β-methoxyethyl ester 5-isopropyl ester of melting point 125°C (petroleum ether/ acetic ester) was obtained. Yield 49% of theory.

brand name

Nimotop (Bayer).

Therapeutic Function

Vasodilator

General Description

Nimodipine, 1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl)- 3,5-pyridinedicarboxylic acid 2-methoxyethyl1-methylethyl ester (Nimotop), is another dihydropyridinecalcium channel blocker but differs in that it dilatesthe cerebral blood vessels more effectively than do the otherdihydropyridine derivatives. This drug is indicated for treatmentof subarachnoid hemorrhage-associated neurologicaldeficits.

Biological Activity

L-type Ca 2+ channel blocker.

Biochem/physiol Actions

Nimodipine enhances the survival of dopaminergic substantia nigra neurons.

Pharmacokinetics

Nimodipine belongs to the class of pharmacological agents known as calcium channel blockers. Nimodipine is indicated for the improvement of neurological outcome by reducing the incidence and severity of ischemic deficits in patients with subarachnoid hemorrhage from ruptured congenital aneurysms who are in good neurological condition post-ictus (e.g., Hunt and Hess Grades I-III). The contractile processes of smooth muscle cells are dependent upon calcium ions, which enter these cells during depolarization as slow ionic transmembrane currents. Nimodipine inhibits calcium ion transfer into these cells and thus inhibits contractions of vascular smooth muscle. In animal experiments, nimodipine had a greater effect on cerebral arteries than on arteries elsewhere in the body perhaps because it is highly lipophilic, allowing it to cross the blood brain barrier.

Clinical Use

Calcium-channel blocker:
Prevention and treatment of ischaemic neurological deficits following subarachnoid haemorrhage

Drug interactions

Potentially hazardous interactions with other drugs
Aminophylline: possibly increases aminophylline concentration.
Anaesthetics: enhanced hypotensive effect.
Antibacterials: metabolism accelerated by rifampicin; metabolism possibly inhibited by clarithromycin, erythromycin and telithromycin.
Antidepressants: enhanced hypotensive effect with MAOIs .
Antiepileptics: effect reduced by carbamazepine,
barbiturates, phenytoin and primidone.
Antifungals: metabolism possibly inhibited by itraconazole and ketoconazole; negative inotropic effect possibly increased with itraconazole.
Antihypertensives: enhanced hypotensive effect, increased risk of first dose hypotensive effect of post synaptic alpha-blockers.
Antivirals: concentration possibly increased by ritonavir; use telaprevir with caution.
Grapefruit juice: concentration increased - avoid.
Theophylline: possibly increased theophylline concentration.

Metabolism

Hepatic metabolism via CYP 3A4.

Metabolism

Nimodipine is extensively metabolised in the liver via the cytochrome P450 isoenzyme CYP3A4. It is eliminated as metabolites, mainly by dehydrogenation of the dihydropyridine ring and oxidative O-demethylation. Oxidative ester cleavage, hydroxylation of the 2- and 6-methyl groups, and glucuronidation as a conjugation reaction are other important metabolic steps. The three primary metabolites occurring in plasma show no or only therapeutically negligible residual activity. The metabolites are excreted about 50% renally and 30% in faeces via the bile.

storage

Store at RT

References

1) Cohen and McCarthy (1987),?Nimodipine block of calcium channels in rat anterior pituitary cells; J. Physiol.,?387?195 2) Batuecas?et al.?(1998),?Effects of chronic nimodipine on working memory of old rats in relation to defects in synaptosomal calcium homeostasis; Eur. J. Pharmacol.,?350?141 3) LeVere?et al.?(1989),?Recovery of function after brain damage: facilitation by the calcium entry blocker nimodipine; Behav. Neurosci.,?103?561 4) Herzfeld?et al.?(2014),?Investigation of the neuroprotective impact of nimodipine on Neuro2a cells by means of a surgery-like stress model; Int. J. Mol. Sci.,?15?18453 5) Schampel?et al.?(2017),?Nimodipine fosters remyelination in a mouse model of multiple sclerosis and induces microglia-specific apoptosis; Proc. Natl. Acad. Sci. USA,?114?E3295 6) Allen?et al.?(1983),?Cerebral arterial spasm – a controlled trial of nimodipine in patients with subarachnoid hemorrhage; N. England J. Med.,?308?619