Cetirizine Dosing Reference — Paediatric & Adult India
| Age group | Dose | Frequency | Max/day | Formulation |
|---|---|---|---|---|
| 6–12 months | 2.5 mg | Once daily | 2.5 mg | 0.25 ml of 5mg/5ml syrup |
| 1–2 years | 2.5 mg | Once daily (or BD if needed) | 5 mg | 2.5 ml of 5mg/5ml syrup |
| 2–6 years | 2.5 mg BD or 5 mg OD | Once or twice daily | 5 mg | 2.5 ml BD or 5 ml OD |
| 6–12 years | 5 mg BD or 10 mg OD | Once or twice daily | 10 mg | 5 ml BD / 5mg tab BD / 10mg tab OD |
| Adult / child ≥12 yr | 10 mg | Once daily (evening) | 10 mg | 1 × 10mg tab or 10 ml syrup |
| Adult — renal CrCl 30–49 | 5 mg | Once daily | 5 mg | 5mg tab or 5 ml syrup |
| Adult — renal CrCl 11–30 | 5 mg | Every 48h (alternate days) | 5 mg | 5mg tab |
Cetirizine — Clinical Guide for Indian Doctors & Parents
Cetirizine is a second-generation H1-receptor antagonist and one of the most widely prescribed antihistamines in India for children and adults. Unlike first-generation antihistamines (chlorphenamine, promethazine), cetirizine causes minimal sedation at therapeutic doses due to poor blood-brain barrier penetration. It provides effective once-daily relief for allergic rhinitis, urticaria, atopic eczema-related pruritus, and allergic conjunctivitis. It is available as Zyrtec, Alerid, Cetzine, and Okacet across Indian pharmacies.
In paediatric practice, cetirizine is one of the safest and most evidence-backed antihistamines from 6 months of age. The IAP and BNF endorse its use from infancy. The syrup formulation (5 mg/5 ml) allows accurate weight-based or age-based dosing for young children. Importantly, cetirizine does not have the antimuscarinic side effects (urinary retention, dry mouth, blurred vision, sedation) of older antihistamines like chlorphenamine — making it the preferred first-line antihistamine in children.
Paediatric dosing — age-based guide India
For infants aged 6–12 months: 2.5 mg (2.5 ml of 5mg/5ml syrup) once daily. For children 1–2 years: 2.5 mg once daily, increasing to twice daily if needed. For children 2–6 years: 2.5 mg twice daily or 5 mg once daily. For children 6–12 years: the dose doubles to 5 mg twice daily or 10 mg once daily. Weight-based dosing (0.25 mg/kg/dose, max 5 mg per dose for children under 6, max 10 mg per dose for children over 6) is useful for children whose weight falls outside the typical range for their age.
Cetirizine vs levocetirizine — which to prescribe?
Levocetirizine is the R-enantiomer of cetirizine and is approximately twice as potent. The standard adult dose of levocetirizine is 5 mg once daily (compared to 10 mg for cetirizine). For children aged 6 months to 5 years: levocetirizine 1.25 mg (half a 2.5 mg tablet) once daily; for ages 6–11 years: 2.5 mg once daily. Levocetirizine has a slightly cleaner pharmacokinetic profile and marginally less sedation. In clinical practice, both drugs are equally effective at equivalent doses — choice is often driven by availability and cost. Levocetirizine brands in India include Levocet, Xyzal, and Lecope.
Chronic urticaria — up-dosing strategy
For chronic spontaneous urticaria (CSU) that does not respond to standard doses, international guidelines (EAACI/WAO) recommend up-dosing cetirizine to 20–40 mg/day (off-label) before escalating to omalizumab or immunosuppressants. In India, where CSU is common and biologic therapy is often cost-prohibitive, up-dosed cetirizine (20 mg/day in two divided doses) is a widely used and reasonably effective intermediate step. This should be done under specialist supervision with monitoring for sedation.