Isradipine

Drug Information: Isradipine

Detailed information regarding Isradipine, a dihydropyridine calcium channel blocker primarily used to treat hypertension. Isradipine works by selectively blocking calcium influx into vascular smooth muscle cells and, to a lesser extent, cardiac muscle cells. This leads to vasodilation, a reduction in peripheral vascular resistance, and subsequently, a lowering of blood pressure. Isradipine’s relatively high vascular selectivity makes it useful in managing high blood pressure while minimizing some of the cardiac side effects associated with less selective calcium channel blockers.

Category

Antihypertensive

Mechanism of Action

Isradipine is a calcium channel blocker, specifically a dihydropyridine. Calcium channel blockers inhibit the influx of calcium ions into cells through voltage-gated calcium channels. These channels are crucial for muscle contraction in both cardiac and smooth muscle tissue. Isradipine primarily targets L-type calcium channels located in vascular smooth muscle.

By blocking calcium influx, Isradipine prevents the intracellular calcium concentration from rising, which is necessary for smooth muscle contraction. This leads to relaxation of the arterial smooth muscle, causing vasodilation (widening of blood vessels). This vasodilation reduces peripheral vascular resistance, which in turn lowers blood pressure.

Unlike some other calcium channel blockers, Isradipine has a greater affinity for vascular smooth muscle compared to cardiac muscle. This selectivity contributes to its effectiveness in lowering blood pressure with a potentially lower risk of direct cardiac depressant effects like decreased heart rate that can be seen with non-dihydropyridine calcium channel blockers such as verapamil or diltiazem. It’s important to note that while Isradipine exhibits vascular selectivity, it can still have some effects on cardiac function, especially at higher doses. The reduced blood pressure also reduces the workload on the heart, offering a secondary benefit in certain cardiac conditions.

Clinical Uses

The primary clinical use of Isradipine is the treatment of hypertension (high blood pressure). By dilating blood vessels, it effectively lowers blood pressure, reducing the risk of cardiovascular events like stroke, heart attack, and kidney damage associated with uncontrolled hypertension. It may be used as a monotherapy or in combination with other antihypertensive medications to achieve optimal blood pressure control. While primarily used for hypertension, Isradipine, like other calcium channel blockers, has also been investigated for other conditions. Some studies have explored its potential role in managing certain types of angina (chest pain) and migraine prophylaxis, although it is not a first-line treatment for these conditions. Its use in these areas is less common compared to its use in hypertension. The decision to use Isradipine should always be made in consultation with a healthcare professional, considering the patient’s individual medical history and other medications.

Dosage

Adults: The typical starting dose of Isradipine is 2.5 mg twice daily. Depending on the individual’s response and blood pressure control, the dose may be gradually increased to a maximum of 10 mg twice daily. Doses above 20 mg daily are generally not recommended. Isradipine is administered orally.

Pediatrics: The safety and efficacy of Isradipine in pediatric patients have not been definitively established. Use in pediatric patients is generally not recommended.

Indications

* Hypertension (High Blood Pressure)

Contraindications

* Hypersensitivity to Isradipine or other dihydropyridine calcium channel blockers.
* Severe hypotension (systolic blood pressure less than 90 mmHg).
* Advanced aortic stenosis.

FAQ

Q: What is Isradipine used for?
A: Isradipine is primarily used to treat high blood pressure (hypertension).

Q: How does Isradipine work?
A: Isradipine works by blocking calcium channels in blood vessel walls, causing the vessels to relax and widen, which lowers blood pressure.

Q: What are the common side effects of Isradipine?
A: Common side effects can include headache, dizziness, flushing, and swelling of the ankles and feet.

Q: Can I take Isradipine with other medications?
A: You should always inform your doctor about all the medications you are taking, including over-the-counter drugs and supplements, as Isradipine can interact with other medications.

Q: What should I do if I miss a dose of Isradipine?
A: If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not double the dose to catch up.

Q: Can I drink alcohol while taking Isradipine?
A: It is generally advised to limit or avoid alcohol consumption while taking Isradipine, as alcohol can enhance the blood pressure-lowering effect of the medication and increase the risk of side effects like dizziness.

Q: Does Isradipine affect my heart rate?
A: Isradipine has a relatively small impact on heart rate compared to some other calcium channel blockers.

Q: How long does it take for Isradipine to start working?
A: Isradipine typically starts to lower blood pressure within a few hours of taking a dose, but it may take several weeks to achieve the full effect.