Bilazest 20 Tablet is used to treat various kinds of allergic symptoms like blocked/runny/itchy nose, red/watery eyes, and skin rashes. It contains Bilastine which blocks the effects of histamine, a chemical messenger naturally involved in allergic reactions. Thus, it helps to relieve the discomfort and unpleasant symptoms that occur due to allergic conditions. It may cause side effects such as abdominal pain, headache, dizziness, dry mouth, sore throat, nausea, cold-like nose symptoms (in children), or diarrhoea (in children). Before taking this medicine, you should tell your doctor if you are allergic to any of its components or if you are pregnant/breastfeeding, and about all the medications you are taking and pre-existing medical conditions.