Brief Answer: Some actionables to prevent allergy. Detailed Answer: Hi, If a person has more than 3 bouts of cold and runny nose in a year it is uncommon. I could see that you are allergic to dust and smog. If allergy could be reason for cold and runny nose there is a need to keep away from allergens. That is the perfect or perhaps the only way to prevent these recurrent bouts. Simple measures bring in a great relief for you: 1) Cover nose, mouth, ears and hair from dust while you go out. The mucus membranes and hair attract dust a lot. 2) Once you enter home/office immediately wash nostrils, mouth, ears with warm saline water. You can prepare it easily with 30ml of warm water with pinch of salt in it. This measure prevents the triggers 3) The medicines that you take will not prevent further triggers but help to reduce the current symptoms alone. They do not prevent allergy. 4) Wash bedsheets, curtains etc frequently in 100 degree hot water, at least once a week. Suppose if these do not help, there could be some other allergens causing the issue. You can find that out with patch tests or blood tests. You should see an Allergy / ENT specialist to find them. Hope this answer is useful.

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