Relent Tablet 15's contains Cetirizine and ambroxol, which are both used to treat coughs. An allergy is an immune system reaction to external substances that are normally not damaging to your body. These alien substances are referred to as "allergens." Everybody has a different level of allergy. Some people could have dietary allergies as well as seasonal allergies like hay fever. Others may have allergies to pet dander or pollen. Cough is one of the signs of allergies. When mucus or any external irritant gets in the throat, a reflexive coughing motion takes place. Cetirizine is a member of the antihistamine or anti-allergic drug class.Disclaimer:For more information contact your physician.