Zyrtec Rapid Acting 24 hour Hayfever Allergy Relief Antihistamine Mini Tablets relieve hayfever allergy symptoms and are small and easy to swallow. When your immune system takes offence to an outside particle or substance, your body produces antibodies to attack this normally harmless substance by releasing a chemical called histamine. Zyrtec contains the active ingredient, cetirizine, which helps to block the production of histamines to relieve symptoms of hayfever allergies. Cetirizine is part of a class of medications called antihistamines. Zyrtec Hayfever Allergy Mini Tablets provide fast powerful 24 hour relief of hayfever allergy symptoms, including: - Sneezing - Runny, itchy nose - Red, itchy and watery eyes - Post nasal drip Zyrtec is effective against seasonal hayfever triggers, such as: - Grass Pollen - Tree Pollen - Weed Pollen 24 Hour Relief Allergy & Hayfever Tablets 10 Pack Rapid Acting Antihistamine