Zyrtec

Cetirizine hydrochloride.

FC tab: Each film-coated tablet contains 10 mg of cetirizine hydrochloride.
Excipients/Inactive Ingredients: FC tab: Microcrystalline cellulose, Lactose monohydrate, Colloidal anhydrous silica, Magnesium stearate, Hydroxypropylmethylcellulose, Titanium dioxide, Macrogol 400.

FC tab: Zyrtec Tablets 10mg are indicated in adults and paediatric patients 6 years and above: for the relief of nasal and ocular symptoms of seasonal and perennial allergic rhinitis; for the relief of symptoms of chronic idiopathic urticaria.
Oral soln: Adults and Children ≥2 Years: Symptomatic treatment of seasonal or perennial allergic rhinitis, ocular pruritus, tearing and redness of eyes, as well as chronic urticaria.

FC tab: Posology: 10mg once daily (1 tablet).
Special population: Older people: Data do not suggest that the dose needs to be reduced in elderly subjects provided that the renal function is normal.
Patients with moderate to severe renal impairment: There are no data to document the efficacy/safety ratio in patients with renal impairment. Since cetirizine is mainly excreted via renal route, in cases no alternative treatment can be used, the dosing intervals must be individualized according to renal function. Refer to the following table and adjust the dose as indicated. To use this dosing table, an estimate of the patient's creatinine clearance (Cl_cr) in ml/min is needed. The Cl_cr (ml/min) may be estimated from serum creatinine (mg/dl) determination using the following formula: See equation and Table 1.

Click on icon to see table/diagram/image


Click on icon to see table/diagram/image

Patients with hepatic impairment: No dose adjustment is needed in patients with solely hepatic impairment. In patients with hepatic impairment and renal impairment, adjustment of the dose is recommended (see Patients with moderate to severe renal impairment as previously mentioned).
Paediatric population: The tablet formulation should not be used in children under 6 years of age as it does not allow the necessary dose adjustments.
Children aged 6 to 12 years: 5 mg twice daily (a half tablet twice daily).
Adolescents above 12 years: 10 mg once daily (1 tablet).
In paediatric patients suffering from renal impairment, the dose will have to be adjusted on an individual basis taking into account the renal clearance, age and body weight of the patient.
Method of administration: The tablets need to be swallowed with a glass of liquid.
Oral soln: Adults and Adolescents >12 years: Recommended Dose: 10 mg once daily.
Children 6-12 years: Either 5 mg twice daily or 10 mg single dose in the evening; >30 kg: 10 mg daily; ≤30 kg: 5 mg daily.
In individual cases, it maybe possible to divide the dose into 2 separate amounts (ie, 5 mg in the morning and evening).
Children 2-6 years: 2.5 mg twice daily (administered as 2.5 mL oral solution twice daily).
In the absence of pharmacokinetic and safety information for cetirizine in children <6 years with impaired renal or hepatic function, its use in this impaired patient population is not recommended.
Patients with Impaired Renal Function: The dosing intervals must be individualized according to renal function. Refer to the following and adjust the dose as indicated. To use the dose adjustment, an estimate of the patient's creatinine clearance (Cl_cr) in mL/min is needed. The Cl_cr (mL/min) may be estimated from serum creatinine (mg/dL) determination using the following formula:

Click on icon to see table/diagram/image

Dose adjustment in patients with impaired renal function:
Normal (≥80 mL/min) and Mild (50-79 mL/min): 10 mg daily.
Moderate (30-49 mL/min): 10 mg every 2 days.
Severe (10-29 mL/min): 10 mg every 3 days.
End-Stage Renal Disease and Patients Undergoing Dialysis (<10 mL/min): Contraindicated.
Patients with Impaired Hepatic Function: In patients ≥12 years with impaired hepatic function, a dose of 5 mg once daily is recommended. Similarly, pediatric patients 6-11 years with impaired hepatic function should use the lower recommended dose.
It is advisable to take Zyrtec with a little liquid during the evening meal since the symptoms for which the product is given usually appear during the night. In patients affected by side effects, the dose may be taken as 5 mg in the morning and 5 mg in the evening.
10 mL solution = 10 mg; 5 mL solution = 5 mg; 2.5 mL solution = 2.5 mg.

Symptoms: Symptoms observed after an overdose of cetirizine are mainly associated with CNS effects or with effects that could suggest an anticholinergic effect.
Adverse events reported after an intake of at least 5 times the recommended daily dose are: confusion, diarrhoea, dizziness, fatigue, headache, malaise, mydriasis, pruritus, restlessness, sedation, somnolence, stupor, tachycardia, tremor and urinary retention.
Management: There is no known specific antidote to cetirizine.
Should overdose occur, symptomatic or supportive treatment is recommended. Gastric lavage may be considered shortly after ingestion of the drug.
Cetirizine is not effectively removed by haemodialysis.

FC tab: Cetirizine is contraindicated in: hypersensitivity to the active substance, to any of the excipients listed in Description, to hydroxyzine or to any piperazine derivatives; patients with severe renal impairment with a creatinine clearance below 10 ml/min.
Oral soln: History of hypersensitivity to cetirizine or to any of the excipients of Zyrtec; to hydroxyzine or to any piperazine derivatives.
Patients with severe renal impairment of (Cl_cr <10 mL/min), rare hereditary problems of galactose intolerance, Lapp-lactase deficiency or glucose-galactose malabsorption should not take Zyrtec tablet.
Patients with rare hereditary problems of fructose intolerance should not take Zyrtec oral solution.

FC tab: Alcohol: At therapeutic doses, no clinically significant interactions have been demonstrated with alcohol (for a blood alcohol level of 0.5 g/L). Nevertheless, precaution is recommended if alcohol is taken concomitantly.
Increased risk of urinary retention: Caution should be taken in patients with predisposition factors of urinary retention (e.g. spinal cord lesion, prostatic hyperplasia) as cetirizine may increase the risk of urinary retention.
Patients at risk of convulsions: Caution is recommended in epileptic patients and patients at risk of convulsions.
Allergy skin tests: Response to allergy skin tests are inhibited by antihistamines and a wash-out period (of 3 days) is required before performing them.
Excipients: Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take cetirizine film-coated tablets.
Skin reactions: Pruritus and/or urticaria may occur when cetirizine is stopped, even if those symptoms were not present before treatment initiation. In some cases, the symptoms may be intense and may require treatment to be restarted. The symptoms should resolve when the treatment is restarted.
Effects on ability to drive and use machines: Objective measurements of driving ability, sleep latency and assembly line performance have not demonstrated any clinically relevant effects at the recommended dose of 10 mg. However, patients who experience somnolence should refrain from driving, engaging in potentially hazardous activities or operating machinery. They should not exceed the recommended dose and should take their response to the medicinal product into account.
Use in children: The use of the film-coated tablet formulation is not recommended in children aged less than 6 years since this formulation does not allow for appropriate dose adaptation. It is recommended to use Zyrtec Oral Solution.
Oral soln: At therapeutic doses, no clinically significant interactions have been demonstrated with alcohol (for a blood alcohol level of 0.5 g/L). Nevertheless, precaution is recommended if alcohol is taken concomitantly.
Caution in epileptic patients and patients at risk of convulsions is recommended.
Methyl parahydroxybenzoate and propyl parahydroxybenzoate included in the oral solution may cause allergic reactions (possibly delayed).
Effects on the Ability to Drive or Operate Machinery: Objective measurements of driving ability, sleep latency and assembly line performance have not demonstrated any clinically relevant effects at the recommended dose of 10 mg.
Patients intending to drive, engaging in potentially hazardous activities or operating machinery should not exceed the recommended dose and should take their response to the medicinal product into account.
In sensitive patients, concurrent use with alcohol or other CNS depressants may cause additional reductions in alertness and impairment of performance.
Use in children: The use of the Zyrtec film-coated tablet is not recommended in children <6 years since Zyrtec does not allow for appropriate dose adaptation. It is recommended to use a paediatric formulation of cetirizine.
Due to the amount of some excipients in the formulation, the oral solution is not recommended in children <2 years.

Fertility: Limited data is available on human fertility but no safety concern has been identified.
Animal data show no safety concern for human reproduction.
Pregnancy: For cetirizine prospectively collected data on pregnancy outcomes do not suggest potential for maternal or foetal/embryonic toxicity above background rates.
Animal studies do not indicate direct or indirect harmful effects with respect to pregnancy, embryonal/foetal development, parturition or postnatal development. Caution should be exercised when prescribing to pregnant women.
Lactation: Cetirizine is excreted in human milk at concentrations representing 25% to 90% of those measured in plasma, depending on sampling time after administration. Therefore, caution should be exercised when prescribing cetirizine to lactating women.

Clinical Studies: Overview: Clinical studies have shown that cetirizine at the recommended dosage has minor undesirable effects on the CNS, including somnolence, fatigue, dizziness and headache. In some cases, paradoxical CNS stimulation has been reported.
Although cetirizine is a selective antagonist of peripheral H1-receptors and is relatively free of anticholinergic activity, isolated cases of micturition difficulty, eye accommodation disorders and dry mouth have been reported.
Instances of abnormal hepatic function with elevated hepatic enzymes accompanied by elevated bilirubin have been reported. Mostly this resolves upon discontinuation of the treatment with cetirizine hydrochloride.
Listing of ADRs: Double blind controlled clinical trials comparing cetirizine to placebo or other antihistamines at the recommended dosage (10 mg daily for cetirizine), of which quantified safety data are available, included more than 3200 subjects exposed to cetirizine.
From this pooling, the following adverse reactions were reported for cetirizine 10 mg in the placebo-controlled trials at rates of 1.0 % or greater: See Table 2.

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Although statistically more common than under placebo, somnolence was mild to moderate in the majority of cases. Objective tests as demonstrated by other studies have demonstrated that usual daily activities are unaffected at the recommended daily dose in healthy young volunteers.
Paediatric population: Adverse reactions at rates of 1 % or greater in children aged from 6 months to 12 years, included in placebo-controlled clinical trials are: See Table 3.

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Post-marketing experience: In addition to the adverse reactions reported during clinical studies and listed previously, the following undesirable effects have been reported in post-marketing experience.
Undesirable effects are described according to MedDRA System Organ Class and by estimated frequency based on post-marketing experience.
Frequencies are defined as follows: Very common ≥1/10; Common ≥1/100 to <1/10; Uncommon ≥1/1000 to <1/100; Rare ≥1/10000 to <1/1000; Very rare <1/10000; Not known (cannot be estimated from the available data).
Blood and lymphatic disorders: Very rare: thrombocytopenia.
Immune system disorders: Rare: hypersensitivity.
Very rare: anaphylactic shock.
Metabolism and nutrition disorders: Not known: increased appetite.
Psychiatric disorders: Uncommon: agitation.
Rare: aggression, confusion, depression, hallucination, insomnia.
Very rare: tics.
Not known: suicidal ideation, nightmare.
Nervous system disorders: Uncommon: paraesthesia.
Rare: convulsions.
Very rare: dysgeusia, dyskinesia, dystonia, syncope, tremor.
Not known: amnesia, memory impairment.
Eye disorders: Very rare: accommodation disorder, blurred vision, oculogyration.
Ear and labyrinth disorders: Not known: vertigo.
Cardiac disorders: Rare: tachycardia.
Gastro-intestinal disorders: Uncommon: diarrhoea.
Hepatobiliary disorders: Rare: hepatic function abnormal (increased transaminases, alkaline phosphatase, γ-GT and bilirubin).
Not known: hepatitis.
Skin and subcutaneous tissue disorders: Uncommon: pruritus, rash.
Rare: urticaria.
Very rare: angioneurotic oedema, fixed drug eruption.
Not known: acute generalized exanthematous pustulosis.
Musculoskeletal and connective tissue disorders: Not known: arthralgia.
Renal and urinary disorders: Very rare: dysuria, enuresis.
Not known: urinary retention.
General disorders and administration site conditions: Uncommon: asthenia, malaise.
Rare: oedema.
Investigations: Rare: weight increased.
Description of selected adverse reactions: After discontinuation of cetirizine, pruritus (intense itching) and/or urticaria have been reported.

Due to the pharmacokinetic, pharmacodynamic and tolerance profile of cetirizine, no interactions are expected with this antihistamine. Neither pharmacodynamic nor significant pharmacokinetic interaction was reported in drug-drug interactions studies performed, notably with pseudoephedrine or theophylline (400mg/day).
The extent of absorption of cetirizine is not reduced with food, although the rate of absorption is decreased.
In sensitive patients, the concurrent use of alcohol or other CNS depressants may cause additional reductions in alertness and impairment of performance, although cetirizine does not potentiate the effect of alcohol (0.5 g/L blood levels).

Antihistamines & Antiallergics

R06AE07 - cetirizine ; Belongs to the class of piperazine derivatives used as systemic antihistamines.

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