Levocetirizine Dihydrochloride

Pronunciation: LEE-voe-se-TIR-i-zeen dye-HYE-droe-KLOR-ide
Class: Antihistamine

Trade Names

Xyzal
- Tablets 5 mg
- Solution, oral 0.5 mg/mL

Pharmacology

Inhibition of H ₁ receptors.

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Pharmacokinetics

Absorption

Rapidly and extensively absorbed. T _max is 0.9 h. C _max is 270 and 308 ng/mL after single and repeated once-daily dosing, respectively. Steady state achieved after 2 days. Food delayed T _max by approximately 1.25 h and decreased C _max by approximately 36%.

Distribution

Plasma protein binding is approximately 92%. Vd is approximately 0.4 L/kg.

Metabolism

Metabolism is less than 14% and by aromatic oxidation, N- and O-dealkylation, and taurine conjugation.

Elimination

The half-life is about 8 to 9 h. Elimination is 85.4% and 12.9% via urine and feces, respectively. Excreted both by glomerular filtration and active tubular secretion.

Special Populations

Dosage should be reduced in patients with renal function impairment.

Has not been studied; however, because levocetirizine is primarily excreted unchanged by the kidneys, it is unlikely that the Cl will be decreased in patients with hepatic function impairment.

Pharmacokinetic data are limited. Total body Cl was approximately 33% lower in 9 elderly subjects, compared with younger adults. Adjust dose in accordance with renal function.

In children 6 to 11 yr of age, C _max and AUC values were about 2-fold greater than in adults. Total body Cl was 30% greater and elimination half-life was 24% shorter when compared with adults.

Half-life was slightly shorter in women than in men; however, the body weight–adjusted oral Cl in women appears to be comparable with that in men.

Pharmacokinetics are similar among racial groups.

Indications and Usage

Relief of symptoms associated with seasonal and perennial allergic rhinitis; treatment of uncomplicated skin manifestations of chronic idiopathic urticaria.

Contraindications

Patients with ESRD (CrCl less than 10 mL/min) and patients undergoing hemodialysis; children 6 to 11 yr of age with renal impairment; hypersensitivity to any component of the product or to certirizine.

Dosage and Administration

PO 2.5 to 5 mg once daily in the evening (max, 5 mg once daily).

PO 2.5 mg (½ tablet or 1 teaspoon oral solution) once daily in the evening (max, 2.5 mg once daily).

1.25 mg (½ teaspoon oral solution) once daily in the evening (max, 1.25 mg once daily).

PO 2.5 to 5 mg once daily in the evening (max, 5 mg once daily).

PO 2.5 mg (½ tablet or 1 teaspoon oral solution) once daily in the evening (max, 2.5 mg once daily).

PO 1.25 mg (½ teaspoon oral solution) once daily in the evening (max, 1.25 mg once daily).

PO

2.5 mg once daily.

2.5 mg once every other day.

2.5 mg twice weekly, separated by 3 to 4 days.

Do not administer.

General Advice

• May be taken without respect to food.
• Measure and administer prescribed dose of oral solution using dosing syringe, dosing spoon, or dosing cup.

Storage/Stability

Store at 68° to 77°F; excursions permitted between 59° and 86°F.

Drug Interactions

No formal in vivo drug-drug interaction studies have been performed with levocetirizine. Drug interaction studies have been performed with racemic cetirizine.

Additive CNS depressant effects; concurrent use should be avoided.

Food had no effect on the extent of levocetirizine exposure; however, the half-life was delayed about 1.25 hours and the C _max was decreased about 36% after administration with a high-fat meal. Levocetirizine may be taken without regard to food.

Cetirizine AUC and half-life may be increased, while Cl may be decreased. The risk of adverse reactions may be increased.

May decrease cetirizine Cl.

Laboratory Test Interactions

None well documented.

Adverse Reactions

Cardiovascular

Palpitations (postmarketing).

CNS

Somnolence (6%); fatigue, pyrexia (4%); aggression, agitation, convulsion (postmarketing).

Dermatologic

Fixed-drug eruption, pruritus, rash, urticaria (postmarketing).

EENT

Nasopharyngitis (6%); otitis media (3%); epistaxis, pharyngitis (2%); visual disturbances (postmarketing).

GI

Diarrhea, vomiting (4%); dry mouth (3%); nausea (postmarketing).

Hepatic

Hepatitis (postmarketing).

Musculoskeletal

Myalgia (postmarketing).

Respiratory

Cough (3%); dyspnea (postmarketing).

Miscellaneous

Anaphylaxis, angioneurotic edema, hypersensitivity (postmarketing).

Precautions

Pregnancy

Category B .

Lactation

Undetermined; however, cetirizine has been reported to be excreted in breast milk.

Children

Safety and efficacy not established in children younger than 2 yr of age for the treatment of seasonal allergic rhinitis or in children younger than 6 mo of age for the treatment of perennial allergic rhinitis and chronic idiopathic urticaria.

Elderly

Use with caution, usually starting at the low end of the dosage range, because of the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant diseases or other drug therapy.

Renal Function

Dosage should be reduced in patients with renal function impairment.

Hazardous Tasks

Patients should avoid engaging in hazardous tasks requiring complete mental alertness and motor coordination, such as operating machinery or driving a vehicle.

Overdosage

Symptoms

Drowsiness in adults; agitation and restlessness followed by drowsiness in children.

Patient Information

• Advise patient that drug may cause drowsiness or impaired judgment or thinking skills, and to use caution while driving, riding a bike, or performing other tasks requiring mental alertness.
• Advise patients to avoid alcohol or other CNS depressants because additional reduction in alertness may occur.

Copyright © 2009 Wolters Kluwer Health.