Levocetirizine

Levocetirizine is a Second generation Antihistaminic and selective H1 Receptor Anatagonsit belonging to Antihistamine.

Levocetirizine is used in the treatment of Allergic rhinitis, Allergic conjunctivitis and Urticaria, chronic spontaneous.

Levocetirizine is rapidly absorbed after oral administration, with peak plasma concentrations occurring within 0.9-2 hours. The absolute bioavailability of Levocetirizine is approximately 100%. Levocetirizine is widely distributed throughout the body and is not significantly bound to plasma proteins. Levocetirizine is extensively metabolized in the liver by O-dealkylation to form the inactive metabolite, descarboethoxyloratadine. The elimination half-life of Levocetirizine is about 8-10 hours in adults and may be prolonged in patients with impaired renal function. Levocetirizine and its metabolites are primarily eliminated in the urine, with a small amount eliminated in the feces.

Onset: 1 hour.

Duration: 24 hours.

Tmax of Levocetirizine is approximately 0.9 to 2.0 hours after oral administration.

Cmax of Levocetirizine after a single oral dose of 5 mg is approximately 270 ng/mL

Levocetirizine shows common side effects like insomnia, confusion, hallucination, nervousness, disorientation, depression, anxiety, mood changes. Renal and urinary disorders: Crystalluria (high doses).

Levocetirizine is available in tablets, Solution

Levocetirizine is available in India, Germany, Canada, France.

Levocetirizine is a second generation histamine H1 antagonist used to treat various allergic symptoms. It has a long duration of action as it is generally taken once daily, and a wide therapeutic window as animal studies show the maximal nonlethal dose is over 100x a normal dose. Patients are cautioned to avoid tasks that require complete alertness, avoid alertness, and use caution in patients with factors predisposing urinary retention.

Levocetirizine is available in the form of tablets and oral solutions.

Tablets: Levocetirizine tablets should be taken with or without water.

Levocetirizine is used in the treatment of Allergic rhinitis, Allergic conjunctivitis and Urticaria, chronic spontaneous.

Levocetirizine, an antihistamine and is an active enantiomer of cetirizine. Its binding affinity to H₁-receptor is twice than cetirizine. It selectively competes for H₁-receptor sites on effector cells in the gastrointestinal tract, blood vessels and respiratory tract.

Levocetirizine is approved for use in the following clinical indications

Allergic rhinitis (OTC only): Temporary relief of symptoms due to hay fever or other respiratory allergies (including rhinitis, sneezing, itchy/watery eyes, or itching of the throat/nose) in adults and pediatric patients ≥2 years of age.

Allergic rhinitis, perennial: Relief of symptoms associated with perennial allergic rhinitis in pediatric patients 6 months to 2 years of age.

Urticaria, chronic spontaneous: Treatment of uncomplicated skin manifestations of chronic spontaneous urticaria in adults and pediatric patients ≥6 months of age.

Although not approved there has been certain off label use documented for Levocetirizine which includes:

Urticaria, new onset

Levocetirizine is available in the dosage strength of 5mg, 2.5 mg/5 mL

Levocetirizine is available in the form of

• Tablets: Levocetirizine tablets are available in strengths of 5 mg and are taken orally with or without food, usually once daily.
• Oral solution: Levocetirizine oral solution is available in a concentration of 5 mg/5 mL and is taken orally with or without food, usually once daily.
• Disintegrating tablets: Levocetirizine disintegrating tablets are available in strengths of 5 mg and are designed to dissolve quickly in the mouth without the need for water. They can be taken with or without food, usually once daily.

Dosage Adjustment in Kidney Patient

• The renal dosing recommendations are based upon the best available evidence and clinical expertise. (Senior Editorial Team: Bruce Mueller, PharmD, FCCP, FASN, FNKF; Jason Roberts, PhD, BPharm (Hons), B App Sc, FSHP, FISAC; Michael Heung, MD, MS).

• CrCl >80 mL/minute: No dosage adjustment necessary.

• CrCl 50 to 80 mL/minute: 2.5 mg once daily.

• CrCl 30 to 50 mL/minute: 2.5 mg once every other day.

• CrCl 10 to 30 mL/minute: 2.5 mg twice weekly (every 3 or 4 days).

• CrCl <10 mL/minute: Use is contraindicated.

Dosage Adjustment in Hepatic impairment Patient

● No Dosage Adjustment is necessary .

Dosage Adjustment for Pediatric Patients:

Allergic rhinitis, perennial: Oral:

• Infants ≥6 months and Children ≤5 years: 1.25 mg once daily (in the evening); maximum daily dose: 1.25 mg/day; Note: In children >2 years, dosing based on previous FDA approved manufacturer labelling.
• Children ≥6 years and Adolescents
• 6 to 11 years: 2.5 mg once daily (in the evening); maximum daily dose: 2.5 mg/day
• ≥12 years: 5 mg once daily (in the evening); some patients may experience relief of symptoms with 2.5 mg once daily

Hay fever and other respiratory allergies: OTC labeling:

Oral:

• Children 2 to 5 years: 1.25 mg once daily (in the evening); maximum daily dose: 1.25 mg/day
• Children 6 to 11 years: 2.5 mg once daily (in the evening); maximum daily dose: 2.5 mg/day
• Children ≥12 years and Adolescents: 2.5 to 5 mg once daily (in the evening); dose based on symptom severity; maximum daily dose: 5 mg/day

Urticaria, chronic: Oral:

• Infants ≥6 months and Children ≤5 years: 1.25 mg once daily (in the evening); maximum daily dose: 1.25 mg/day
• Children 6 to 11 years: 2.5 mg once daily (in the evening); maximum daily dose: 2.5 mg/day
• Children ≥12 years and Adolescents: 5 mg once daily (in the evening); some patients may experience relief of symptoms with 2.5 mg once daily

Allergic perennial rhinitis, chronic urticaria:

Infants ≥6 months and Children ≤11 years: Contraindicated with any degree of renal impairment.

Children ≥12 years and Adolescents:

CrCl >80 mL/minute: No adjustment necessary

CrCl 50 to 80 mL/minute: 2.5 mg once daily

CrCl 30 to 50 mL/minute: 2.5 mg once every other day

CrCl 10 to 30 mL/minute: 2.5 mg twice weekly (every 3 or 4 days)

CrCl <10 mL/minute or on hemodialysis: Contraindicated

Hemodialysis: Nondialyzable

Hay fever and other respiratory allergies (OTC): Children ≥2 years and Adolescents: Use is not recommended.

Take after eating and with a full glass of water to decrease gastric upset.

Levocetirizine is contraindicated in individuals who have previously exhibited hypersensitivity or allergic reactions to Levocetirizine or any of its components. It is also contraindicated in individuals with end-stage renal disease (ESRD) who are undergoing hemodialysis, as the drug is eliminated primarily through the kidneys and may accumulate in the body in these patients. Additionally, the use of Levocetirizine is not recommended in individuals with severe hepatic impairment, as there is limited data on the safety and efficacy of the drug in this population. It is important to consult with a healthcare provider before taking any medication to ensure that it is safe and appropriate for individual use.

Levocetirizine is a prescription medication used to treat allergic symptoms such as sneezing, runny nose, itching, and watery eyes. It is an antihistamine that works by blocking the action of histamine, a substance in the body that causes allergic symptoms.

• Here are some important warnings and precautions to keep in mind when taking Levocetirizine: Allergic reactions: Some people may have an allergic reaction to Levocetirizine. If you experience symptoms such as hives, difficulty breathing, or swelling of the face, lips, tongue, or throat, seek immediate medical attention.
• Drowsiness: Levocetirizine can cause drowsiness and impair your ability to drive or operate heavy machinery. Do not drive or perform tasks that require mental alertness until you know how Levocetirizine affects you.
• Pregnancy and breastfeeding: Levocetirizine should only be used during pregnancy or breastfeeding if the benefits outweigh the risks. Consult your healthcare provider before using Levocetirizine if you are pregnant or breastfeeding.
• Liver and kidney problems: Levocetirizine is primarily eliminated from the body by the liver and kidneys. If you have liver or kidney problems, your doctor may adjust your dose of Levocetirizine. Other medications: Levocetirizine can interact with other medications, including antidepressants, sleeping pills, and muscle relaxants. Inform your healthcare provider about all medications, vitamins, and supplements you are taking before starting Levocetirizine.
• Alcohol: Avoid drinking alcohol while taking Levocetirizine. Alcohol can increase the sedative effects of Levocetirizine.
• Older adults: Older adults may be more sensitive to the side effects of Levocetirizine, especially drowsiness. Always follow your doctor's instructions when taking Levocetirizine and report any side effects or unusual symptoms to your healthcare provider.

Levocetirizine may cause liver problems, and using it with substantial quantities of ethanol may increase that risk.

Levocetirizine is an antihistamine medication that is commonly used to treat allergies and allergic reactions. While there is limited information on the safety of Levocetirizine use during breastfeeding, the drug is generally considered to be compatible with breastfeeding.

Pregnancy Category B

Levocetirizine is classified as pregnancy category B by the US Food and Drug Administration (FDA). This means that animal studies have not shown any harm to the fetus, but there are no well-controlled studies in pregnant women.

Oral formulations should be administered on an empty stomach with water (at least 1 hour before or 2 hours after meals, milk, or other dairy products). Maintain fluid intake to ensure adequate hydration and urinary output.

• Common Adverse effects

Irritation in the nose or throat (with nasal spray) Hoarseness or changes in voice (with inhalation) Headache Nausea Cough Sore throat Runny or stuffy nose Sinus pain Dry mouth or throat Skin rash or itching (with topical use)

• Less Common Adverse effects:

Allergic reactions, including hives, itching, or difficulty breathing Eye problems, such as cataracts or glaucoma (with long-term use) Growth suppression in children (with long-term use) High blood sugar levels Increased risk of infections, including fungal infections of the mouth or throat (thrush) Mood changes or behavioral changes, such as agitation or aggression Osteoporosis or bone fractures (with long-term use) Slow wound healing

• Rare Adverse effects

Adrenal suppression (with long-term use) Anaphylaxis (a severe and life-threatening allergic reaction) Cushing's syndrome (with long-term use) Decreased immune system function (with long-term use) Hyperglycemia (high blood sugar levels) Hypokalemia (low levels of potassium in the blood) Hypersensitivity reactions (such as rash or angioedema) Ocular toxicity (such as increased intraocular pressure, cataracts, or glaucoma with long-term use) Psychiatric effects (such as mood changes or suicidal thoughts)

Levocetirizine is generally considered to have a low potential for drug interactions due to its low affinity for cytochrome P450 enzymes and minimal plasma protein binding. However, it is still important to be aware of the following potential drug interactions: Levocetirizine may enhance the sedative effects of central nervous system (CNS) depressants, such as alcohol, benzodiazepines, and opioids. Levocetirizine may increase the plasma concentrations of drugs that are substrates of the organic cation transporter 2 (OCT2), such as metformin and dofetilide. Levocetirizine may also interact with certain antibiotics, such as erythromycin and clarithromycin, which may increase its plasma concentrations.

The common side effects of Levocetirizine include the following :

Irritation in the nose or throat (with nasal spray) Hoarseness or changes in voice (with inhalation) Headache Nausea Cough Sore throat Runny or stuffy nose Sinus pain Dry mouth or throat Skin rash or itching (with topical use).

Symptoms: Drowsiness; agitation, restlessness (children).

Management: Symptomatic and supportive. Gastric lavage may be considered shortly following ingestion.

Pharmacodynamic

Levocetirizine is a second generation histamine H₁ antagonist used to treat various allergic symptoms. It has a long duration of action as it is generally taken once daily, and a wide therapeutic window as animal studies show the maximal nonlethal dose is over 100x a normal dose. Patients are cautioned to avoid tasks that require complete alertness, avoid alertness, and use caution in patients with factors predisposing urinary retention.

Pharmacokinetics

• Absorption: Levocetirizine is rapidly absorbed after oral administration, with peak plasma concentrations occurring within 0.9-2 hours. The absolute bioavailability of Levocetirizine is approximately 100%.
• Distribution: Levocetirizine is widely distributed throughout the body and is not significantly bound to plasma proteins.
• Metabolism: Levocetirizine is extensively metabolized in the liver by O-dealkylation to form the inactive metabolite, descarboethoxyloratadine.
• Excretion: The elimination half-life of Levocetirizine is about 8-10 hours in adults and may be prolonged in patients with impaired renal function. Levocetirizine and its metabolites are primarily eliminated in the urine, with a small amount eliminated in the feces.

1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1364710/
2. https://reference.medscape.com/drug/colestid-Levocetirizine -342452
3. https://go.drugbank.com/drugs/DB00375
4. https://www.sciencedirect.com/topics/medicine-and-dentistry/Levocetirizine
5. https://europepmc.org/article/med/6988203