Cetirizine vs Sildenafil

## Cetirizine vs Sildenafil: Overview

This comparison examines the pharmacological differences between **Cetirizine** and **Sildenafil**.

## Mechanism of Action

**Cetirizine**: Second-generation H1 antihistamine.

**Sildenafil**: Selective PDE5 inhibitor increasing cGMP.

## Pharmacokinetics

**Half-life**: Cetirizine — 6.5-10 hours; Sildenafil — 4 hours.

## Chemical Properties

**Molecular Formula**: Cetirizine — C21H25ClN2O3; Sildenafil — C22H30N6O4S.

**Molecular Weight**: Cetirizine — 388.8900 g/mol; Sildenafil — 474.5800 g/mol.

**Type**: Cetirizine — Small molecule; Sildenafil — Small molecule.