Clarinex 5 mg Tablets

Brand name

The trade name of the drug is Clarinex. It is used to identify this drug in the pharmaceutical market and is widely known among doctors and patients.

International Nonproprietary Name (INN)

The international nonproprietary name is desloratadine. This name reflects the active active ingredient of the drug and is used in international medical practice.

Form of release

Clarinex is available in several forms for ease of use: coated tablets of 5 mg, packed in blisters of 10 or 30 pieces; syrup with a concentration of 0.5 mg/mL, supplied in bottles of 60 ml or 120 ml with a measuring spoon; as well as mouth-soluble tablets (dispersible) of 2.5 mg or 5 mg, designed for rapid action. Each form is designed to meet the needs of different patient populations.

Composition

Active ingredient

The main active ingredient is desloratadine. One tablet contains 5 mg of desloratadine, 1 ml of syrup contains 0.5 mg, and dispersible tablets contain 2.5 mg or 5 mg, depending on the dosage.

Auxiliary Components

The tablets include substances such as lactose monohydrate, microcrystalline cellulose, corn starch, magnesium stearate, and a coating of hypromellose, titanium dioxide, and polyethylene glycol. The syrup contains sorbitol, propylene glycol, citric acid, sodium benzoate (preservative) and flavoring. The dispersible tablets consist of mannitol, aspartame, crospovidone and flavoring additives.

Pharmacologic Properties

Pharmacodynamics

Desloratadine is a selective peripheral H1-histamine receptor blocker with long-lasting antihistamine action. It prevents the binding of histamine to receptors, which prevents the development of allergic reactions such as tissue swelling, mucus hypersecretion and inflammation. The drug also has anti-inflammatory properties, reducing the production of pro-inflammatory cytokines and leukocyte adhesion in allergy foci. Unlike first-generation antihistamines, desloratadine practically does not penetrate the blood-brain barrier, which minimizes the sedative effect. The therapeutic effect begins 30 minutes after administration and persists for up to 24 hours, providing the convenience of a single use per day.

Pharmacokinetics

Absorption

Desloratadine is rapidly absorbed from the gastrointestinal tract after oral administration. The maximum concentration in blood plasma is reached in 2-4 hours. Bioavailability is about 80-90%, and food intake does not significantly affect the rate or completeness of absorption.

Distribution

The drug actively binds to plasma proteins (83-87%), mainly to albumin. The volume of distribution is about 49 l/kg, which indicates good penetration into the tissues of the body, except for the central nervous system.

Metabolism

Desloratadine is metabolized in the liver by cytochrome P450 enzymes (CYP3A4 and CYP2D6) to form the active metabolite, 3-hydroxydesloratadine, which then undergoes glucuronidation. This process ensures the prolonged action of the drug.

Excretion

The half-life of desloratadine is 20-30 hours in adults, which allows to maintain a stable concentration in the blood at a single intake. The drug is excreted through the kidneys (about 47%) and intestine (about 53%) in the form of metabolites. Less than 2% of the substance is excreted unchanged.

Indications for Use

Clarinex is used for the treatment of the following conditions:

• Seasonal allergic rhinitis caused by plant pollen (hay fever);
• Year-round allergic rhinitis associated with household allergens (dust, feathers, animal hair);
• Chronic idiopathic urticaria with manifestations of itching and skin rashes;
• Symptomatic relief of allergic reactions, including nasal congestion, sneezing and lacrimation.

The drug is effective in adults and children, providing rapid relief of symptoms and long-term allergy control.

Contraindications

The use of Clarinex is prohibited in the following cases:

• Individual intolerance to desloratadine or auxiliary components;
• Severe renal insufficiency (creatinine clearance less than 10 ml/min);
• Phenylketonuria (for dispersible tablets due to aspartame content);
• Children less than 6 months of age (for syrup) or less than 2 years of age (for dispersible tablets);
• Pregnancy and breastfeeding (due to lack of safety data).

The drug is administered with caution to patients with impaired liver function or epilepsy.

Method of Administration and Dosage

How to take

Clarinex tablets are taken orally, drinking a small amount of water (50-100 ml). Food intake does not affect the effectiveness, so the drug can be taken at any time of day. Syrup is measured with the provided spoon or syringe and taken orally, preferably at the same time of day. The dispersible tablets are placed on the tongue, where they dissolve quickly and are then swallowed without water.

Dosages for adults and children

Adults and children over 12 years of age

The recommended dose is 5 mg (1 tablet or 10 mL of syrup) once daily.

Children 6 to 11 years of age

The recommended dose is 2.5 mg (5 mL of syrup or 1 2.5 mg dispersible tablet) once daily.

Children 1 to 5 years of age

The dose is 1.25 mg (2.5 mL syrup) once daily.

Children 6 months to 11 months

Dosage is 1 mg (2 ml syrup) once a day.

Dose adjustment for certain conditions

Moderate renal or hepatic impairment usually does not require dose adjustment, but in severe impairment (creatinine clearance less than 30 ml/min) it is recommended to reduce the frequency of administration to 5 mg every other day under medical supervision.

Side Effects

Clarinex is well tolerated, but the following adverse reactions may occur:

• General: fatigue, headache, dry mouth;
• Gastrointestinal: nausea, abdominal discomfort, rarely - diarrhea;
• Nervous system: insomnia or drowsiness (in isolated cases);
• Allergic reactions: skin rash, itching, extremely rare - angioedema;
• Other: increase in liver enzymes (reversible).

The side effects are usually mild and pass independently without withdrawal of the drug.

Overdose

Symptoms of overdose

Overdose of Clarinex is rare, but drowsiness, dizziness, palpitations and confusion may occur when taking doses significantly higher than the therapeutic dose (e.g., more than 20 mg).

First aid measures

If an overdose is suspected, discontinue the drug and seek medical attention. Prior to medical assistance, the stomach may be washed (if less than one hour has elapsed) and activated charcoal may be given to reduce absorption.

Drug Interactions

Influence on the effects of other drugs

Desloratadine has no significant effect on the metabolism of other drugs because it interacts weakly with CYP450 enzymes. However, when coadministered with ketoconazole or erythromycin, a slight increase in the concentration of desloratadine in the blood is possible, which does not require dose adjustment.

Compatibility with alcohol and food

Alcohol does not enhance the effect of Clarinex, which distinguishes it from many antihistamines. Food does not affect the pharmacokinetics, which allows taking the drug regardless of food intake.

Special Precautions

Use in pregnancy and breastfeeding

Data on the safety of Clarinex in pregnancy are limited, so the drug is not recommended. Desloratadine penetrates into breast milk, and breastfeeding should be discontinued for the duration of treatment.

Effects on driving and mechanisms

Clarinex rarely causes drowsiness, but patients should evaluate their reaction to the drug before driving or operating machinery.

Particulars of use in the elderly and children

In elderly patients, the drug excretion may be delayed, which requires medical supervision. For children, the dosage is selected strictly according to age and body weight, using syrup in younger age groups.