Development and Validation of Rapid and Cost-Effective RP-HPLC/UV Method for Determination of Cetirizine/Levocetirizine in Blood Plasma of Smokers and Non Smokers: a Two Cohort Comparative Study

In this research study, a simple, rapid, sensitive, and cost-effective Reverse Phase High Performance Liquid Chromatography method was developed and validated for determination of Cetirizine and Levocetirizine in human plasma. The drugs were separated on an ACE Generix100-5 C18 RP (250 × 4.6 mm, 5 μm) column, using Acetonitrile and Distilled water pH 7 (59:41 v/v) as mobile phase with a flow rate of 1.5 mL/min, retention time of 3.39 ± 0.02 min, detection wavelength of 230 nm, and column oven temperature at 26°C. The drug was extracted from human plasma using Methanol, the percent recovery was 97%. The LOD and LOQ for Cetirizine and Levocetirizine were 0.5 ng and 1 ng. The method was linear over the concentration range of 0.5-1000 ng /mL for Cetirizine and Levocetirizine. The method was applied for analysis of drugs in plasma following oral administration of Cetirizine (10 mg) and Levocetirizine (5 mg) in smokers and nonsmokers of Pashtun ethnicity belonging from different districts of Khyber Pakhtunkhwa, Pakistan. The difference between Cetirizine plasma levels in smokers and non-smokers was significant with p -value 0.0279.