Luvistin

Usage

Luvistin, containing levocabastine hydrochloride, is an antihistamine primarily prescribed for the treatment of allergic conjunctivitis. It belongs to the pharmacological classification of ophthalmic antihistamines. Levocabastine works by selectively blocking H1-receptors in the conjunctiva, thereby reducing the effects of histamine released during an allergic reaction. This action helps alleviate the symptoms of allergic conjunctivitis, such as itching, redness, and tearing.

Alternate Names

Levocabastine hydrochloride is the generic name. A popular brand name is Livostin.

How It Works

Pharmacodynamics: Levocabastine exerts its therapeutic effect by selectively antagonizing H1-receptors in the ocular tissues. This inhibits the histamine-mediated vasodilation, capillary permeability increase, and itching sensation associated with allergic reactions.

Pharmacokinetics:

• Absorption: After topical ocular administration, levocabastine is systemically absorbed, reaching peak plasma concentrations within 1 to 2 hours.
• Metabolism: It is moderately metabolized in the liver via cytochrome P450 enzymes, though the main elimination pathway is through renal excretion of the unchanged drug.
• Elimination: Primarily eliminated renally (about two-thirds) and through fecal excretion (about one-third). The elimination half-life is about 35 to 40 hours.

Mode of Action: Levocabastine binds to H1-receptors on the surface of mast cells and basophils, preventing histamine from binding and triggering the allergic cascade. This reduces the release of inflammatory mediators and the symptoms of allergic conjunctivitis.

Dosage

Standard Dosage

Adults: The standard dosage is one drop of 0.05% levocabastine hydrochloride ophthalmic suspension instilled in each affected eye four times daily.

Children: The safety and efficacy in children below the age of 12 have not been fully established. Use with caution under the guidance of a doctor.

Special Cases:

• Elderly Patients: No specific dosage adjustments are typically required unless renal or hepatic impairment exists.
• Patients with Renal Impairment: Caution is advised, and dose reduction may be necessary.
• Patients with Hepatic Dysfunction: Dose reduction may be considered in severe hepatic impairment.
• Patients with Comorbid Conditions: No specific adjustments indicated, but careful monitoring is recommended.

Clinical Use Cases

• Intubation, Surgical Procedures, Mechanical Ventilation, ICU Use, Emergency Situations: Levocabastine is not typically indicated for these scenarios.

Dosage Adjustments:

Dose modifications should be individualized based on the patient’s response and clinical presentation. Renal and hepatic function should be considered, especially in elderly patients.

Side Effects

Common Side Effects:

• Ocular: Mild transient burning or stinging upon instillation, blurred vision, eye irritation, headache.

Rare but Serious Side Effects:

• Hypersensitivity reactions (e.g., angioedema, urticaria).

Long-Term Effects:

No specific long-term adverse effects have been reported with regular use of levocabastine ophthalmic suspension.

Adverse Drug Reactions (ADR):

Clinically significant ADRs are rare but may include severe ocular irritation or allergic reactions, requiring prompt discontinuation and medical attention.

Contraindications

• Known hypersensitivity to levocabastine hydrochloride or any component of the formulation.

Drug Interactions

No significant drug interactions have been reported with topical levocabastine.

Pregnancy and Breastfeeding

• Pregnancy Safety Category: Category C. Use only if potential benefit justifies risk to the fetus.
• Breastfeeding: Levocabastine is excreted in breast milk in small amounts. Use cautiously during breastfeeding.

Drug Profile Summary

• Mechanism of Action: Selective H1-receptor antagonist.
• Side Effects: Mild burning/stinging, blurred vision, eye irritation, headache (rarely, hypersensitivity).
• Contraindications: Hypersensitivity.
• Drug Interactions: None significant.
• Pregnancy & Breastfeeding: Category C; use with caution.
• Dosage: 1 drop in each affected eye four times daily.
• Monitoring Parameters: Monitor for ocular irritation or allergic reactions.

Popular Combinations:

Often used alone. No specific commonly prescribed combinations are established.

Precautions

• Contact lens wearers should remove lenses before instillation and wait at least 15 minutes before reinserting.
• Avoid touching the tip of the bottle to the eye or other surfaces.
• Monitor for signs of hypersensitivity.

FAQs (Frequently Asked Questions)

Q1: What is the recommended dosage for Luvistin?

A: One drop in each affected eye four times a day.

Q2: Can I use Luvistin while wearing contact lenses?

A: No, remove lenses before instillation and wait 15 minutes.

Q3: What are the common side effects?

A: Mild burning or stinging, blurred vision, eye irritation.

Q4: Can pregnant or breastfeeding women use Luvistin?

A: Use with caution after consulting a doctor; category C.

Q5: How does Luvistin work?

A: It blocks H1-receptors, reducing allergic reactions in the eye.

Q6: Is Luvistin safe for long-term use?

A: Generally considered safe for long-term use as directed.

Q7: What should I do if I experience severe eye irritation?

A: Discontinue use and consult a doctor immediately.

Q8: Can I use Luvistin with other eye drops?

A: Consult a doctor about combining with other eye medications.

Q9: What is the active ingredient in Luvistin?

A: Levocabastine hydrochloride.