Cetihis

Clear, colorless syrup with banana-grape flavor.

Pharmacology: In animals, Cetirizine dihydrochloride has been shown to be an anti-H₁ agent devoid of any significant anticholinergic or antiserotonin effects. At active doses, it does not induce sedation or behavioral changes.
Cetirizine dihydrochloride will inhibit certain effects produced by exogenous histamine. Cetirizine hydrochloride inhibits the effects produced by endogenous histamine released in vivo. It inhibits the cutaneous reaction induced by Vasoactive Intestinal Polypeptide and substance P, neuropeptides.
Cetirizine dihydrochloride inhibits the histamine-induced "early" phase of the allergic reaction. It also significantly reduces the migration of inflammatory cells e.g., eosinophils and the release of mediators associated with the "late" allergic response.
Cetirizine dihydrochloride reduces bronchial hyperreactivity to histamine in the asthmatic patient. It also reduces the allergic reaction induced by specific allergens. These effects are obtained without any central effects.
Pharmacokinetics: Peak blood levels reached between 30 and 60 minutes after administration of 10 mg Cetirizine hydrochloride. It is strongly bound to plasma proteins.

Adults and children of 2 years and above: Symptomatic treatment of seasonal allergic rhinitis, perennial allergic rhinitis, and urticaria of allergic region.

The solution can be swallowed as such.
Route of Administration: 10 mg (10 mL of oral solution) once daily.
A 5 mg starting dose (5 mL of oral solution) may be proposed if this leads to satisfactory control of the symptoms.
Children: Children aged from 2 to 6 years: 2.5 mg (2.5 mL of oral solution bid) twice daily.
Children aged from 6 to 12 years: 5 mg (5 mL of oral solution) twice daily.
Children over 12 years of age: 10 mg (10 mL of oral solution) once daily.
Elderly: Data does 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: 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 tablet and adjust the dose as indicated. (See equation.)

Click on icon to see table/diagram/image

Dosing adjustments for adult patients with impaired renal function: (See Table 1.)

Click on icon to see table/diagram/image

In pediatric 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.
Patients with hepatic impairment: No dose adjustment is needed in patients with solely hepatic impairment.
Patients with hepatic impairment and renal impairment: Dose adjustment is recommended (see Table 1 as previously mentioned).

Symptoms and signs: Symptoms observed after an important 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, diarrhea, dizziness, fatigue, headache, malaise, mydriasis, pruritus, restlessness, sedation, somnolence, stupor, tachycardia, tremor, and urinary retention.
Treatment: There is no known specific antidote to Cetirizine.
Should overdose occur, symptomatic or supportive treatment is recommended.
Cetirizine is not effectively removed by hemodialysis.
Management should be as clinically indicated or as recommended by the national poison centre, where available.

Cetirizine is contraindicated in: Hypersensitivity to any of the constituents of this formulation, to Hydroxyzine or to any Piperazine derivatives; Patients with end-stage renal disease with eGFR (Estimated Glomerular Filtration Rate) below 15 mL/min.

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 (see Interactions).
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 (see Side Effects).
Patients at risk of convulsions: Caution in epileptic patients and patients at risk of convulsions is recommended.
Skin reactions: Pruritus and/or urticaria may occur when Cetirizine is stopped, even if those symptoms were not present before treatment initiation (see Side Effects). In some cases, the symptoms may be intense and may require treatment to be restarted. The symptoms should resolve when the treatment is restarted.
Allergy skin tests: Allergy skin tests are inhibited by antihistamines and a wash-out period of 3 days is recommended before performing them.
Food: The extent of absorption of Cetirizine is not reduced with food, although the rate of absorption is decreased.
Activities requiring mental alertness: In clinical trials, the occurrence of somnolence has been reported in some patients taking Cetirizine. Due caution should therefore be exercised when driving a car or operating potentially dangerous machinery.

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: Caution should be exercised when prescribing to pregnant women. For Cetirizine, prospectively collected data on pregnancy outcomes do not suggest potential for maternal or fetal/embryonic toxicity above background rates.
Animal studies do not indicate direct or indirect harmful effects with respect to pregnancy, embryonal/fetal development, parturition, or postnatal development.
Lactation: Cetirizine passes into breast milk. A risk of side effects in breastfed infants cannot be excluded. Caution should be exercised when prescribing Cetirizine to lactating women. Cetirizine is excreted in human milk at concentrations representing 25% to 90% of those measured in plasma, depending on sampling time after administration.

Post Marketing Data: Adverse drug reactions (ADRs) are listed as follows by MedDRA system organ class and by frequency.
Frequencies are defined as: Very common (≥1/10); Common (≥1/100 to <1/10); Uncommon (≥1/1,000 to <1/100); Rare (≥1/10,000 to <1/1,000); Very rare (<1/10,000); Not known (cannot be estimated from the available data). (See Table 2.)

Click on icon to see table/diagram/image

Skin reactions occurring after discontinuation of Cetirizine: After discontinuation of Cetirizine, pruritus (intense itching) and/or urticaria have been reported (see Precautions).

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 interaction studies performed, notably with Pseudoephedrine or Theophylline (400 mg/day).
Alcohol and other CNS depressants: 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) (see Precautions).

Store at temperature of not more than 30°C.

Antihistamines & Antiallergics

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

C