Acitrin

Indications

Acitrin is prescribed to alleviate symptoms of seasonal and perennial allergic rhinitis. It is also effective in managing uncomplicated skin conditions caused by chronic idiopathic urticaria and allergen-induced asthma.
Please use this medication only as advised by a registered physician.

Pharmacology

Cetirizine Hydrochloride, the active ingredient in Acitrin, is a powerful H1 receptor antagonist with minimal anticholinergic or antiserotonergic effects. At therapeutic doses, it causes negligible drowsiness and does not alter behavior. It works by blocking the early-phase histamine response in allergic reactions and reducing the migration of inflammatory cells and mediators responsible for late-phase allergic responses.

Pharmacokinetics:

• A 10 mg dose of Cetirizine reaches peak plasma concentration (257 mcg/L in adults; 980 mcg/L in children) within one hour.
• Food does not interfere with its absorption but may slightly slow its rate.
• Peak blood levels of 0.3 micrograms/ml occur 30 to 60 minutes after a 10 mg dose.
• Plasma half-life: approximately 11 hours.
• Renal clearance: 30 ml/min, with an excretion half-life of 9 hours.
• Consistent absorption is observed across individuals.

Dosage & Administration

Oral Dosage:

• Adults & Children 6 years and older: 1 tablet or 2 teaspoonfuls daily (or 1 teaspoonful twice daily).
• Children 2-6 years: 1 teaspoonful daily or ½ teaspoonful twice daily.
• Children 6 months-2 years: ½ teaspoonful daily; for children aged 12-23 months, the dose may be increased to ½ teaspoonful every 12 hours.

Injectable Dosage:
Cetirizine injectable is intended for intravenous use only, administered as needed for acute urticaria. Each dose should be given as an intravenous push over 1 to 2 minutes. This form is not recommended for children under 6 years with impaired renal or hepatic function.

• Adults & Adolescents (12 years and older): 10 mg by IV injection once daily.
• Children (6-11 years): 5-10 mg by IV injection based on symptom severity.
• Children (6 months-5 years): 2.5 mg by IV injection.

Please use this medication only as advised by a registered physician.

Drug Interactions

Cetirizine has no clinically significant interactions with Theophylline, Azithromycin, Pseudoephedrine, Ketoconazole, Erythromycin, or similar medications.

Contraindications

Acitrin is contraindicated in individuals with known hypersensitivity to Cetirizine or Hydroxyzine.

Side Effects

The most commonly reported side effect of Acitrin is drowsiness (somnolence).

Pregnancy & Lactation

Cetirizine Hydrochloride falls under US FDA Pregnancy Category B. While animal studies have not shown harm, there are no adequate studies in pregnant women. Use only if absolutely necessary during pregnancy. Since Cetirizine can be excreted in breast milk, caution is advised for nursing mothers.

Precautions & Warnings

• Avoid driving or operating heavy machinery while using this medication.
• Use with caution in patients with mild to moderate liver or kidney impairment, as clearance is reduced. In dialysis patients, the elimination half-life is approximately 20 hours, with a threefold increase in plasma AUC.

Special Populations

• Pediatric Use: Safe for children aged 6 months to 5 years.
• Elderly Use: Clearance is reduced in elderly patients, correlating with reduced creatinine clearance.

Therapeutic Class

Non-sedating Antihistamines.

Storage Guidelines

Store in a dry, cool place away from heat and light. Keep out of reach of children.