Cetirizine
Mechanism :
Cetirizine is an orally active and selective second generation H1-receptor antagonist. Cetirizine, a metabolite of hydroxyzine, is an antihistamine; its principal effects are mediated via selective inhibition of peripheral H1 receptors. It also possesses some mast cell stabilizing properties.
Indication :
- Allergic rhinitis
- Hay fever
- Urticaria
Contraindications :
Cetirizine is contraindicated in those patients with a known hypersensitivity to it or any of its ingredients or hydroxyzine.
Dosing :
6-11 months:
2.5 mg PO OD.
1-6 years:
2.5 mg PO once or twice a day.
6-18 years:
2.5 mg PO once or twice a day.
Adverse Effect :
Somnolence, headache, dizziness, dry mouth.
Interaction :
No clinically significant drug interactions have been found with theophylline at a low dose, azithromycin, pseudoephedrine, ketoconazole, or erythromycin. There was a small decrease in the clearance of cetirizine with larger theophylline doses.
Renal Dose :
Dose in Renal Impairment GFR (mL/min)
| 20-50 | Dose as in normal renal function |
| 10-20 | Dose as in normal renal function |
| <10 | 5–10 mg daily |
Dose in Patients undergoing Renal Replacement Therapies
| CAPD | Unlikely to be dialysed. Dose as in normal renal function |
| HD | Not dialysed. Dose as in GFR<10 mL/min |
| HDF/High flux | Not dialysed. Dose as in GFR<10 mL/min |
| CAV/VVHD | Unknown dialysability. Dose as in normal renal function |
Hepatic Dose :
Children > 6 years: Do not use more than 5 mg PO OD.
Children < 6 years: Use is contraindicated.