Nimodipine

Intravenous
Ischaemic neurological deficits following subarachnoid hemorrhage

Oral
Prophylaxis of neurological deficit following subarachnoid haemorrhage

Oral:
Initially, 30 mg 4 hrly.
Intravenous:
Initially, ≤0.5 mg/hr.

cap: Should be taken on an empty stomach. Take 1 hr before or 2 hr after meals.
tab: May be taken with or without food. Take consistently, either always w/ or always w/o meals.

Incompatible w/ some plastics, including polyvinyl chloride (PVC). It must not be added to an infusion bag or bottle, or be mixed w/ other drugs.

Use w/in 1 mth of MI or an episode of unstable angina. Concomitant use w/ potent CYP3A4 inhibitors (e.g. clarithromycin, ritonavir, ketoconazole, nefazodone).

Patients w/ cerebral oedema or severely raised intracranial pressure. Contents of oral capsules should be given only by mouth or through a feeding tube. It must never be administered IV or by any other parenteral route. Hepatic impairment. Pregnancy and lactation.

Hypotension, oedema, ECG abnormalities, palpitations, rebound vasospasm, flushing, fluid retention, lower abdominal discomfort or cramps, constipation, mental depression, headache, lightheadedness, dizziness, dyspnoea, muscle pain, thrombocytopenia, anaemia, rash, pruritus, haematoma, diaphoresis.

PO: C

Careful monitoring of BP and pulse rate.

Symptoms: Excessive peripheral vasodilation, systemic hypotension, tachycardia, bradycardia, GI complaints, nausea. Management: Symptomatic and supportive treatment. Admin of vasopressor may be necessary if significant hypotension occurs. IV Ca salts have been also used for hypotension.

Plasma concentration and efficacy may be significantly reduced when administered w/ strong CYP3A4 inducers (e.g. rifampicin, carbamazepine, phenobarbital, phenytoin). May increase serum levels and toxicity of phenytoin. Increased plasma concentrations w/ cimetidine or sodium valproate.
Potentially Fatal: Increased risk of significant hypotension w/ concomitant potent CYP3A4 inhibitors (e.g. clarithromycin, ritonavir, ketoconazole, nefazodone).

Increased serum levels w/ grapefruit juice. Decreased serum levels w/ St John's wort.

Description: Nimodipine inhibits inflow of Ca ions into cells by blocking Ca channels or select voltage-sensitive areas resulting in relaxation of vascular smooth muscle and myocardium during depolarisation. Nimodipine has greater action on the cerebral vessels because of its high lipophilicity.
Pharmacokinetics:
Absorption: Rapidly absorbed from the GI tract. Bioavailability: Approx 13%. Time to peak plasma concentration: 1 hr.
Distribution: Crosses blood-brain barrier but concentrations in CSF are lower than those in plasma. Plasma protein binding: >95%.
Metabolism: Hepatically metabolised via CYP3A4 isoenzyme. Undergoes extensive first-pass metabolism.
Excretion: In faeces via bile, via urine (as metabolites). Terminal half-life: Approx 9 hr.

Store between 15-30°C. Protect from light.

Peripheral Vasodilators & Cerebral Activators

Anon. Nimodipine. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 07/01/2014.

Buckingham R (ed). Nimodipine. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 07/01/2014.

McEvoy GK, Snow EK, Miller J et al (eds). Nimodipine. AHFS Drug Information (AHFS DI) [online]. American Society of Health-System Pharmacists (ASHP). https://www.medicinescomplete.com. Accessed 07/01/2014.

Nimodipine Capsule (Caraco Pharmaceutical Laboratories, Ltd.). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 07/01/2014.

Serious Medication Errors from Intravenous Administration of Nimodipine Oral Capsules. U.S. FDA. https://www.fda.gov/. Accessed 07/01/2014.