Nimodipine

Nimodipine is a drug from the class of calcium antagonists, which is used to treat various conditions associated with impaired blood circulation in the brain and peripheral vessels. Here are some of the main indications for the use of nimodipine:

The drug is usually available in the form of oral tablets. The dosage and regimen may vary depending on the specific condition and individual patient characteristics. It is important to follow the doctor's instructions or package directions when using nimodipine and to report any side effects or changes in health status.

Indications Nimodipine

1. Subarachnoid hemorrhage: Nimodipine is widely used as a prophylactic medication after subarachnoid hemorrhage to prevent or reduce the development of cerebral vasospasm, which can lead to impaired blood flow and severe neurologic complications.
2. Cerebral vascular aneurysms and their surgical treatment: After surgical intervention for cerebral vascular aneurysms nimodipine may be prescribed to prevent the development of vasospasm and minimize the risk of complications.
3. Ischemic Stroke: In some cases, nimodipine may be used as part of a comprehensive treatment to improve blood flow to the brain in ischemic stroke.
4. Chronic cerebralischemia: Some studies suggest that nimodipine may be useful in treating chronic cerebral ischemic insufficiency, a condition in which the brain does not receive enough oxygen and nutrients due to chronic decreased blood flow.
5. Other cerebral vascular conditions: Some doctors may also prescribe nimodipine to treat other cerebral vascular conditions, such as migraine or neurologic disorders, although this is not common practice.

Release form

1. Oral tablets: This is the most commonly used form of nimodipine, intended for regular oral administration to achieve a stable therapeutic effect. The tablets are usually taken every 4 hours over a period of time as directed by your doctor.
2. Oral liquid capsules: Like tablets, capsules contain liquid nimodipine and are intended to be taken by mouth. They may be particularly useful for patients who have difficulty swallowing solid dosage forms.
3. Intravenous solution: In some cases, when a rapid therapeutic effect is required or when the patient cannot take the drug by mouth, nimodipine may be administered intravenously. This should only be done under strict medical supervision in a hospital setting due to the risk of serious side effects associated with intravenous administration.

Pharmacodynamics

1. Blocking calcium channels: Nimodipine blocks type L calcium channels, which are found in the smooth muscles of blood vessels. This results in reduced calcium entry into the cells of the vascular wall.
2. Relaxation of vascular muscles: Blocking calcium channels leads to relaxation of vascular smooth muscles, resulting in dilated arteries and improved blood flow to the brain.
3. Improving microcirculation in the brain: Increasing blood flow in the brain helps improve microcirculation, which can be especially helpful in vascular disease and stroke.
4. Anti-edematous effect: Nimodipine may also have an anti-edematous effect, helping to prevent brain edema associated with subarachnoid hemorrhage and other conditions.
5. Neuroprotective effect: Some studies suggest that nimodipine may have neuroprotective properties, helping to reduce nerve tissue damage and improve outcome in a variety of neurologic diseases.

Pharmacokinetics

1. Absorption: Nimodipine is usually taken orally in tablet form. Once taken, it is rapidly absorbed from the gastrointestinal tract. Food may affect the rate and extent of absorption, so it is recommended to take nimodipine before a meal or at least 1-2 hours before a meal.
2. Distribution: Nimodipine has a high degree of binding to plasma proteins (approximately 95%). It is rapidly distributed in body tissues, including the brain.
3. Metabolism: Nimodipine is metabolized in the liver with formation of active metabolites. The major metabolite is desmethylnimodipine. These metabolites may have biological activity and may be further metabolized or excreted unchanged.
4. Excretion: The main route of excretion of nimodipine and its metabolites from the body is renal excretion. A small amount is also excreted with bile.
5. Half-life: The half-life of nimodipine is approximately 2 hours, and for its active metabolite desmethylnimodipine it is approximately 9 hours.
6. Mechanism of Action: Nimodipine blocks L-type calcium channels in vascular smooth muscle. This leads to a decrease in intracellular calcium and relaxation of the vascular wall, which may improve blood flow and reduce peripheral vascular resistance.

Dosing and administration

General recommendations for use and dosage, but it is important to follow your doctor's instructions as they may adjust based on your condition and response to treatment:

Tablets and capsules for oral administration

• The standard adultdosage is usually 60 mg every 4 hours for 21 days, starting as soon as possible after a subarachnoid hemorrhage.
• Tablets or capsules should be swallowed whole, without chewing or breaking, with a small amount of liquid. They can be taken independently of meals, but preferably with food or milk to minimize stomach irritation.

Solution for intravenous injection

• Intravenous nimodipine should only be administered in a hospital setting under strict medical supervision due to the risk of serious side effects such as decreased blood pressure.
• Dosage for intravenous administration may vary and is usually calculated based on clinical need and patient condition.

General recommendations

• During treatment with nimodipine, blood pressure and pulse should be monitored regularly, especially at the start of therapy and during dosage changes.
• Avoid drinking grapefruit juice during treatment with nimodipine as it may increase the concentration of the drug in the blood, increasing the risk of side effects.
• If you miss a dose, take it as soon as possible, but do not take a double dose if it is almost time for your next dose.

Use Nimodipine during pregnancy

The safety of using nimodipine during pregnancy has not been well established.

There are limited studies on the effects of nimodipine on pregnancy and fetal development. Based on the available data, the drug may have potential risks for fetal development. Therefore, the use of nimodipine during pregnancy can be recommended only if the benefit to the mother significantly exceeds the potential risks to the child, and only under strict medical supervision.

Contraindications

1. Hypersensitivity: People with known hypersensitivity to nimodipine or other calcium antagonists should not use this drug because of the risk of allergic reactions.
2. Heart failure: Nimodipine may affect cardiac function, therefore its use may be contraindicated in patients with heart failure, especially in case of severe forms.
3. Hypotension: In low blood pressure (hypotension), the use of nimodipine may aggravate this condition and should therefore be used with caution.
4. Myocardial infarction: Nimodipine may cause vasodilation, which may lead to a decrease in pressure in the coronary arteries and worsen the ischemic situation in myocardial infarction. Therefore, it may be contraindicated in patients with active myocardial infarction.
5. Pregnancy and breastfeeding: The use of nimodipine during pregnancy and breastfeeding requires caution and may require consultation with a physician.
6. Hepatic insufficiency: In patients with severe hepatic dysfunction the use of nimodipine may be limited due to its metabolism in the liver.
7. Children: The safety and efficacy of nimodipine in children have not been established; therefore, its use in this age group may be limited.

Side effects Nimodipine

1. Hypotension (low blood pressure): Nimodipine may cause a drop in blood pressure, which may manifest as dizziness, weakness, fatigue, or even fainting.
2. Blood flushes of the face and neck: In some patients, nimodipine may cause redness of the skin of the face and neck, known as hot flashes.
3. Headache: Patients may experience headache or migraines while taking nimodipine.
4. Tachycardia (fast heartbeat): Some people may experience a fast heartbeat while taking nimodipine.
5. Tremor (shaking): Some patients may experience tremors in the hands or other parts of the body.
6. Tachycardia (fast heartbeat): Some people may experience a fast heartbeat while taking nimodipine.
7. Shortnessof breath: Some patients may experience difficulty breathing or shortness of breath.
8. Anxiety or restlessness: In some people, nimodipine may cause feelings of anxiety or restlessness.
9. Digestive disorders: Nausea, vomiting, diarrhea or other digestive disorders may occur.

Overdose

1. Cardiacproblems: Cardiac arrhythmias such as tachycardia (fast heartbeat), bradycardia (slow heartbeat), arterial hypotension and other heart rhythm disturbances may occur.
2. Heart failure: In severe overdose, heart failure may develop, which is manifested by impaired circulation, edema and difficulty in breathing.
3. Central Nervous System (CNS) Problems: Dizziness, drowsiness, loss of consciousness, convulsions and other neurological symptoms may occur.
4. Other side effects: Respiratory system symptoms (breathing may slow down or stop), psychomotor agitation, muscle weakness, digestive system dysfunction (nausea, vomiting, diarrhea) and others may occur.

Interactions with other drugs

1. Blood pressure-lowering drugs (antihypertensives): Nimodipine may increase the hypotensive effect of other blood pressure-lowering drugs such as antihypertensive agents from the group of beta-blockers, calcium antagonists, ACE inhibitors and diuretics. This may lead to a strong decrease in blood pressure, which requires careful monitoring and possibly dose adjustment.
2. Headache and migraine medications: Co-administration of nimodipine with headache and migraine medications such as triptans (e.g. Sumatriptan) or ergotamine may increase the risk of serious cardiovascular complications such as vasospasms.
3. Drugs metabolized by cytochrome P450: Nimodipine may affect the activity of cytochrome P450 enzymes, which may alter the metabolism of other drugs metabolized by these enzymes. This may increase or decrease the blood concentrations of other drugs and alter their effectiveness or safety.
4. Anticonvulsants: Nimodipine may increase blood concentrations of anticonvulsants such as carbamazepine and phenytoin, which may lead to an increase in their action and risk of undesirable effects.
5. Blood clotting-enhancing drugs: Co-administration of nimodipine with anticoagulants or antiaggregants (e.g. Acetylsalicylic acid) may increase the risk of bleeding.

Storage conditions

1. Temperature: Nimodipine should usually be stored at a controlled room temperature, which is 15 to 30 degrees Celsius (59 to 86 degrees Fahrenheit).
2. Dryness: Store nimodipine in a dry place to avoid moisture, which may adversely affect the quality of the drug.
3. Light: Nimodipine should be stored in a dark place protected from direct sunlight. Exposure to light may impair the quality of the drug.
4. Packaging: Keep nimodipine in the original package or container in which it was delivered from the manufacturer. This will help maintain the quality of the drug and protect it from external influences.
5. Children: Keep nimodipine out of the reach of children to prevent accidental use.
6. Special conditions: In some cases, there may be additional storage recommendations on the package or in the drug instructions. Please refer to these recommendations for more precise information.